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Huang C, Chu LM, Liang B, Wu HL, Li BS, Ren S, Hou ML, Nie HC, Kong LY, Fan LQ, Du J, Zhu WB. Comparative genetic analysis of blood and semen samples in sperm donors from Hunan, China. Ann Med 2025; 57:2447421. [PMID: 39757988 PMCID: PMC11721621 DOI: 10.1080/07853890.2024.2447421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/17/2024] [Accepted: 11/22/2024] [Indexed: 01/07/2025] Open
Abstract
OBJECTIVES At present, most genetic tests or carrier screening are performed with blood samples, and the known carrier rate of disease-causing variants is also derived from blood. For semen donors, what is really passed on to offspring is the pathogenic variant in their sperm. This study aimed to determine whether pathogenic variants identified in the sperm of young semen donors are also present in their blood, and whether matching results for blood are consistent with results for sperm. METHODS We included 40 paired sperm and blood samples from 40 qualified semen donors at the Hunan Province Human Sperm Bank of China. All samples underwent exome sequencing (ES) analysis, and the pathogenicity was assessed according to the American College of Medical Genetics (ACMG) guidelines. Scoring for sperm donation matching, which was based on gene scoring and variant scoring, was also used to assess the consistency of sperm and blood genetic test results. RESULTS A total of 108 pathogenic (P)/likely pathogenic (LP) variants in 82 genes were identified. The highest carrier had 7 variants, and there was also one donor did not carry any P/LP variant. On average, each donor carried 2.7 P/LP variants. Among all the P/LP variants, missense mutation was the dominant type and most of them were located in exonic regions. Chromosome 1 harboured the largest number of variants and no pathogenic copy number variants (CNV) was identified in semen donors. The P/LP variant of all the 40 semen donors was consistent by comparing sperm and blood. Except for one case that was slightly different, the rest simulated matching results for blood were all consistent with results for sperm. CONCLUSIONS It is reasonable to choose either blood or sperm for genetic screening in semen donors.
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Affiliation(s)
- Chuan Huang
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive & Genetic Hospital of International Trust and Investment Corporation (CITIC)-Xiangya, Changsha, China
- NHC Key Laboratory of Human Stem Cell and Reproductive Engineering, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Li-Ming Chu
- Basecare Medical Device Co., Ltd, Suzhou, China
| | - Bo Liang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Hui-Lan Wu
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive & Genetic Hospital of International Trust and Investment Corporation (CITIC)-Xiangya, Changsha, China
| | - Bai-Shun Li
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive & Genetic Hospital of International Trust and Investment Corporation (CITIC)-Xiangya, Changsha, China
| | - Shuai Ren
- Basecare Medical Device Co., Ltd, Suzhou, China
| | | | - Hong-Chuan Nie
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive & Genetic Hospital of International Trust and Investment Corporation (CITIC)-Xiangya, Changsha, China
| | | | - Li-Qing Fan
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive & Genetic Hospital of International Trust and Investment Corporation (CITIC)-Xiangya, Changsha, China
- NHC Key Laboratory of Human Stem Cell and Reproductive Engineering, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Juan Du
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive & Genetic Hospital of International Trust and Investment Corporation (CITIC)-Xiangya, Changsha, China
- NHC Key Laboratory of Human Stem Cell and Reproductive Engineering, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Wen-Bing Zhu
- Clinical Research Center for Reproduction and Genetics in Hunan Province, Reproductive & Genetic Hospital of International Trust and Investment Corporation (CITIC)-Xiangya, Changsha, China
- NHC Key Laboratory of Human Stem Cell and Reproductive Engineering, School of Basic Medical Sciences, Central South University, Changsha, China
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Higuchi Y, Takashima H. Clinical genetics of Charcot-Marie-Tooth disease. J Hum Genet 2023; 68:199-214. [PMID: 35304567 DOI: 10.1038/s10038-022-01031-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/02/2022] [Accepted: 03/06/2022] [Indexed: 02/08/2023]
Abstract
Recent research in the field of inherited peripheral neuropathies (IPNs) such as Charcot-Marie-Tooth (CMT) disease has helped identify the causative genes provided better understanding of the pathogenesis, and unraveled potential novel therapeutic targets. Several reports have described the epidemiology, clinical characteristics, molecular pathogenesis, and novel causative genes for CMT/IPNs in Japan. Based on the functions of the causative genes identified so far, the following molecular and cellular mechanisms are believed to be involved in the causation of CMTs/IPNs: myelin assembly, cytoskeletal structure, myelin-specific transcription factor, nuclear related, endosomal sorting and cell signaling, proteasome and protein aggregation, mitochondria-related, motor proteins and axonal transport, tRNA synthetases and RNA metabolism, and ion channel-related mechanisms. In this article, we review the epidemiology, genetic diagnosis, and clinicogenetic characteristics of CMT in Japan. In addition, we discuss the newly identified novel causative genes for CMT/IPNs in Japan, namely MME and COA7. Identification of the new causes of CMT will facilitate in-depth characterization of the underlying molecular mechanisms of CMT, leading to the establishment of therapeutic approaches such as drug development and gene therapy.
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Affiliation(s)
- Yujiro Higuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
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Wang X, Liu X, Qu M, Li H. Sertoli cell-only syndrome: advances, challenges, and perspectives in genetics and mechanisms. Cell Mol Life Sci 2023; 80:67. [PMID: 36814036 PMCID: PMC11072804 DOI: 10.1007/s00018-023-04723-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 01/11/2023] [Accepted: 02/10/2023] [Indexed: 02/24/2023]
Abstract
Male infertility can be caused by quantitative and/or qualitative abnormalities in spermatogenesis, which affects men's physical and mental health. Sertoli cell-only syndrome (SCOS) is the most severe histological phenotype of male infertility characterized by the depletion of germ cells with only Sertoli cells remaining in the seminiferous tubules. Most SCOS cases cannot be explained by the already known genetic causes including karyotype abnormalities and microdeletions of the Y chromosome. With the development of sequencing technology, studies on screening new genetic causes for SCOS are growing in recent years. Directly sequencing of target genes in sporadic cases and whole-exome sequencing applied in familial cases have identified several genes associated with SCOS. Analyses of the testicular transcriptome, proteome, and epigenetics in SCOS patients provide explanations regarding the molecular mechanisms of SCOS. In this review, we discuss the possible relationship between defective germline development and SCOS based on mouse models with SCO phenotype. We also summarize the advances and challenges in the exploration of genetic causes and mechanisms of SCOS. Knowing the genetic factors of SCOS offers a better understanding of SCO and human spermatogenesis, and it also has practical significance for improving diagnosis, making appropriate medical decisions, and genetic counseling. For therapeutic implications, SCOS research, along with the achievements in stem cell technologies and gene therapy, build the foundation to develop novel therapies for SCOS patients to produce functional spermatozoa, giving them hope to father children.
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Affiliation(s)
- Xiaotong Wang
- Institute of Reproductive Health/Center of Reproductive Medicine, Huazhong University of Science and Technology, Wuhan, 430000, China
- The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Xinyu Liu
- Institute of Reproductive Health/Center of Reproductive Medicine, Huazhong University of Science and Technology, Wuhan, 430000, China
| | - Mengyuan Qu
- Institute of Reproductive Health/Center of Reproductive Medicine, Huazhong University of Science and Technology, Wuhan, 430000, China
| | - Honggang Li
- Institute of Reproductive Health/Center of Reproductive Medicine, Huazhong University of Science and Technology, Wuhan, 430000, China.
- Wuhan Tongji Reproductive Medicine Hospital, Wuhan, 430000, China.
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4
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Azzarà A, Risi Ambrogioni L, Cassano I, Lintas C, Longo UG, Denaro V, Gurrieri F. Genetic Characterization in Familial Rotator Cuff Tear: An Exome Sequencing Study. BIOLOGY 2022; 11:biology11111565. [PMID: 36358266 PMCID: PMC9687989 DOI: 10.3390/biology11111565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 10/14/2022] [Accepted: 10/19/2022] [Indexed: 11/07/2022]
Abstract
Background: multiple gene variants seem to contribute to rotator cuff (RC) tear susceptibility. The aim of the study is to perform an exome sequencing analysis within a family to identify rare gene variants predisposing to the development of RC tear. Material and methods: the exome sequencing was conducted in a family consisting of four individuals, two healthy and the remaining ones with bilateral RC tears. Variants in common among the two affected subjects were selected, and those in common with the healthy subject and those with a frequency >1% were removed. The potential pathogenicity of the variants was investigated using the predictions of several in silico tools from VarSome. Results: the exome sequencing yielded approximately 600,000 variants per patient, subsequently filtered according to frequency <1% and absence of association with other diseases. Removing variants common with the healthy subject, 348 rare variants among 248 genes were identified. Based on the risk of damaging, three candidate genes for RC tear were found: COL23A1, EMILIN3, and HDAC10. Conclusion: this is the first whole-exome sequencing analysis within a family to explore genetic predisposition in RC tear. The results reveal the presence of common damaging variants among affected individuals in the COL23A1, EMILIN3, and HDAC10 genes.
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Affiliation(s)
- Alessia Azzarà
- Research Unit of Medical Genetics, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
| | - Laura Risi Ambrogioni
- Operative Research Unit of Trauma and Orthopaedic Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy
- Research Unit of Trauma and Orthopaedic Surgery, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
| | - Ilaria Cassano
- Research Unit of Medical Genetics, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
| | - Carla Lintas
- Research Unit of Medical Genetics, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
- Operative Research Unit of Medical Genetics, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy
| | - Umile Giuseppe Longo
- Operative Research Unit of Trauma and Orthopaedic Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy
- Research Unit of Trauma and Orthopaedic Surgery, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
- Correspondence: ; Tel.: +39-062-2541-1613; Fax: +39-0622-5411
| | - Vincenzo Denaro
- Operative Research Unit of Trauma and Orthopaedic Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy
- Research Unit of Trauma and Orthopaedic Surgery, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
| | - Fiorella Gurrieri
- Research Unit of Medical Genetics, Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Roma, Italy
- Operative Research Unit of Medical Genetics, Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Roma, Italy
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Li ZD, Abuduxikuer K, Wang L, Hao CZ, Zhang J, Wang MX, Li LT, Qiu YL, Xie XB, Lu Y, Wang JS. Defining pathogenicity of NOTCH2 variants for diagnosis of Alagille syndrome type 2 using a large cohort of patients. Liver Int 2022; 42:1836-1848. [PMID: 35567760 DOI: 10.1111/liv.15292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 04/09/2022] [Accepted: 05/09/2022] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND AIMS Alagille syndrome (ALGS) type 2 caused by mutations in NOTCH2 has genotypic and phenotypic heterogeneity. Diagnosis in some atypical patients with isolated hepatic presentation could be missed. METHODS Using 2087 patients with paediatric liver manifestations, NOTCH2 allele frequencies, in-silico prediction, protein domains and clinical features were analysed to define the pathogenicity of NOTCH2 variants for diagnosis of ALGS type 2. RESULTS Among 2087 patients with paediatric liver manifestations, significantly more NOTCH2 variants were absent in gnomAD in patients with elevated γ-glutamyltransferase (GGT) (p = .041). Significantly more NOTCH2 variants which were absent in gnomAD were located in protein functional domains (p = .038). When missense variants were absent in gnomAD and predicted to be pathogenic by at least three out of seven in-silico tools, they were found to be significantly associated with liver manifestations with elevated GGT (p = .003). Comparing this to patients with likely benign (LB) variants, the patients with likely-pathogenic (LP) variants have significantly more liver manifestations with elevated GGT (p = .0001). Significantly more patients with LP variants had extra-hepatic phenotypes of ALGS compared with those patients with LB variants (p = .0004). CONCLUSION When NOTCH2 variants are absent in gnomAD, null variants and missense variants which were predicted to be pathogenic by at least three in-silico tools could be considered pathogenic in patients with high GGT chronic liver diseases.
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Affiliation(s)
- Zhong-Die Li
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Kuerbanjiang Abuduxikuer
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Li Wang
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Chen-Zhi Hao
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Jing Zhang
- Department of Pediatrics, Jinshan Hospital, Fudan University, Shanghai, China
| | - Meng-Xuan Wang
- Department of Pediatrics, Jinshan Hospital, Fudan University, Shanghai, China
| | - Li-Ting Li
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Yi-Ling Qiu
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Xin-Bao Xie
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Yi Lu
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Jian-She Wang
- The Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China.,Shanghai Key Laboratory of Birth Defect, Shanghai, China
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Vitale G, Mattiaccio A, Conti A, Turco L, Seri M, Piscaglia F, Morelli MC. Genetics in Familial Intrahepatic Cholestasis: Clinical Patterns and Development of Liver and Biliary Cancers: A Review of the Literature. Cancers (Basel) 2022; 14:cancers14143421. [PMID: 35884482 PMCID: PMC9322180 DOI: 10.3390/cancers14143421] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/10/2022] [Accepted: 07/12/2022] [Indexed: 02/06/2023] Open
Abstract
The family of inherited intrahepatic cholestasis includes autosomal recessive cholestatic rare diseases of childhood involved in bile acids secretion or bile transport defects. Specific genetic pathways potentially cause many otherwise unexplained cholestasis or hepatobiliary tumours in a healthy liver. Lately, next-generation sequencing and whole-exome sequencing have improved the diagnostic procedures of familial intrahepatic cholestasis (FIC), as well as the discovery of several genes responsible for FIC. Moreover, mutations in these genes, even in the heterozygous status, may be responsible for cryptogenic cholestasis in both young and adults. Mutations in FIC genes can influence serum and hepatic levels of bile acids. Experimental studies on the NR1H4 gene have shown that high bile acids concentrations cause excessive production of inflammatory cytokines, resistance to apoptosis, and increased cell regeneration, all risk conditions for developing hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). NR1H4 gene encodes farnesoid X-activated receptor having a pivotal role in bile salts synthesis. Moreover, HCC and CCA can emerge in patients with several FIC genes such as ABCB11, ABCB4 and TJP2. Herein, we reviewed the available data on FIC-related hepatobiliary cancers, reporting on genetics to the pathophysiology, the risk factors and the clinical presentation.
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Affiliation(s)
- Giovanni Vitale
- Internal Medicine Unit for the Treatment of Severe Organ Failure, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.T.); (M.C.M.)
- Correspondence:
| | - Alessandro Mattiaccio
- U.O. Genetica Medica, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (A.M.); (A.C.); (M.S.)
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum-University di Bologna, 40138 Bologna, Italy
| | - Amalia Conti
- U.O. Genetica Medica, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (A.M.); (A.C.); (M.S.)
| | - Laura Turco
- Internal Medicine Unit for the Treatment of Severe Organ Failure, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.T.); (M.C.M.)
| | - Marco Seri
- U.O. Genetica Medica, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (A.M.); (A.C.); (M.S.)
- Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum-University di Bologna, 40138 Bologna, Italy
| | - Fabio Piscaglia
- Division of Internal Medicine, Hepatobiliary and Immunoallergic Diseases, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy;
| | - Maria Cristina Morelli
- Internal Medicine Unit for the Treatment of Severe Organ Failure, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy; (L.T.); (M.C.M.)
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Next-Generation Sequencing Advances the Genetic Diagnosis of Cerebral Cavernous Malformation (CCM). Antioxidants (Basel) 2022; 11:antiox11071294. [PMID: 35883785 PMCID: PMC9311989 DOI: 10.3390/antiox11071294] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/24/2022] [Accepted: 06/26/2022] [Indexed: 02/07/2023] Open
Abstract
Cerebral Cavernous Malformation (CCM) is a cerebrovascular disease of genetic origin that predisposes to seizures, focal neurological deficits and fatal intracerebral hemorrhage. It may occur sporadically or in familial forms, segregating as an autosomal dominant condition with incomplete penetrance and highly variable expressivity. Its pathogenesis has been associated with loss-of-function mutations in three genes, namely KRIT1 (CCM1), CCM2 and PDCD10 (CCM3), which are implicated in defense mechanisms against oxidative stress and inflammation. Herein, we screened 21 Italian CCM cases using clinical exome sequencing and found six cases (~29%) with pathogenic variants in CCM genes, including a large 145−256 kb genomic deletion spanning the KRIT1 gene and flanking regions, and the KRIT1 c.1664C>T variant, which we demonstrated to activate a donor splice site in exon 16. The segregation of this cryptic splicing mutation was studied in a large Italian family (five affected and seven unaffected cases), and showed a largely heterogeneous clinical presentation, suggesting the implication of genetic modifiers. Moreover, by analyzing ad hoc gene panels, including a virtual panel of 23 cerebrovascular disease-related genes (Cerebro panel), we found two variants in NOTCH3 and PTEN genes, which could contribute to the abnormal oxidative stress and inflammatory responses to date implicated in CCM disease pathogenesis.
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Susgun S, Kasan K, Yucesan E. Gene Hunting Approaches through the Combination of Linkage Analysis with Whole-Exome Sequencing in Mendelian Diseases: From Darwin to the Present Day. Public Health Genomics 2022; 24:207-217. [PMID: 34237751 DOI: 10.1159/000517102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 04/27/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In the context of medical genetics, gene hunting is the process of identifying and functionally characterizing genes or genetic variations that contribute to disease phenotypes. In this review, we would like to summarize gene hunting process in terms of historical aspects from Darwin to now. For this purpose, different approaches and recent developments will be detailed. SUMMARY Linkage analysis and association studies are the most common methods in use for explaining the genetic background of hereditary diseases and disorders. Although linkage analysis is a relatively old approach, it is still a powerful method to detect disease-causing rare variants using family-based data, particularly for consanguineous marriages. As is known that, consanguineous marriages or endogamy poses a social problem in developing countries, however, this same condition also provides a unique opportunity for scientists to identify and characterize pathogenic variants. The rapid advancements in sequencing technologies and their parallel implementation together with linkage analyses now allow us to identify the candidate variants related to diseases in a relatively short time. Furthermore, we can now go one step further and functionally characterize the causative variant through in vitro and in vivo studies and unveil the variant-phenotype relationships on a molecular level more robustly. Key Messages: Herein, we suggest that the combined analysis of linkage and exome analysis is a powerful and precise tool to diagnose clinically rare and recessively inherited conditions.
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Affiliation(s)
- Seda Susgun
- Department of Medical Biology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkey.,Graduate School of Health Sciences, Istanbul University, Istanbul, Turkey
| | - Koray Kasan
- Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkey
| | - Emrah Yucesan
- Department of Medical Biology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkey
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9
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Current Understanding of the Genetics of Tourette Syndrome. Biomed J 2022; 45:271-279. [PMID: 35042017 PMCID: PMC9250083 DOI: 10.1016/j.bj.2022.01.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 01/09/2022] [Accepted: 01/10/2022] [Indexed: 12/13/2022] Open
Abstract
Gilles de la Tourette syndrome (TS) is a common, childhood-onset psychiatric disorder characterized by persistent motor and vocal tics. It is a heterogeneous disorder in which the phenotypic expression may be affected by environmental factors, such as immune responses. Furthermore, several studies have shown that genetic factors play a vital role in the etiology of TS, as well as its comorbidity with other disorders, including attention deficit hyperactivity disorder, obsessive-compulsive disorder, and autism spectrum disorder. TS has a complex inheritance pattern and, according to various genetic studies, several genes and loci have been correlated with TS. Genome-wide linkage studies have identified Slit and Trk-like 1 (SLITRK1) and histidine decarboxylase (HDC) genes, and candidate gene association studies have extensively investigated the dopamine and serotonin system genes, but there have been no consistent results. Moreover, genome-wide association studies have implicated several genetic loci; however, larger study cohorts are needed to confirm this. Copy number variations, which are polymorphisms in the number of gene copies due to chromosomal deletions or duplications, are considered another significant source of mutations in TS. In the last decade, whole genome/exome sequencing has identified several novel genetic mutations in patients with TS. In conclusion, more studies are needed to reveal the exact mechanisms of underlying TS, which may help to provide more information on the prognosis and therapeutic plans for TS.
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10
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Zhou D, Jia S, Yi L, Wu Z, Song Y, Zhang B, Li Y, Yang X, Xu A, Li X, Zhang W, Duan W, Li Z, Qi S, Chen Z, Ouyang Q, Jia J, Huang J, Ou X, You H. OUP accepted manuscript. Metallomics 2022; 14:6561631. [PMID: 35357466 PMCID: PMC9154322 DOI: 10.1093/mtomcs/mfac024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/29/2022] [Indexed: 11/29/2022]
Abstract
The mutations in modifier genes may contribute to some inherited diseases including Wilson disease (WD). This study was designed to identify potential modifier genes that contribute to WD. A total of 10 WD patients with single or no heterozygous ATP7B mutations were recruited for whole-exome sequencing (WES). Five hundred and thirteen candidate genes, of which the genetic variants present in at least two patients, were identified. In order to clarify which proteins might be involved in copper transfer or metabolism processes, the isobaric tags for relative and absolute quantitation (iTRAQ) was performed to identify the differentially expressed proteins between normal and CuSO4-treated cell lines. Thirteen genes/proteins were identified by both WES and iTRAQ, indicating that disease-causing variants of these genes may actually contribute to the aberrant copper ion accumulation. Additionally, the c.86C > T (p.S29L) mutation in the SLC31A2 gene (coding CTR2) has a relative higher frequency in our cohort of WD patients (6/191) than reported (0.0024 in gnomAD database) in our healthy donors (0/109), and CTR2S29L leads to increased intracellular Cu concentration and Cu-induced apoptosis in cultured cell lines. In conclusion, the WES and iTRAQ approaches successfully identified several disease-causing variants in potential modifier genes that may be involved in the WD phenotype.
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Affiliation(s)
| | | | | | | | - Yi Song
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Bei Zhang
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Yanmeng Li
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Xiaoxi Yang
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Anjian Xu
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Xiaojin Li
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Wei Zhang
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Weijia Duan
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Zhenkun Li
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Saiping Qi
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Zhibin Chen
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | - Qin Ouyang
- Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
- Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China
- National Clinical Research Center for Digestive Diseases, On behalf of China Registry of Genetic/Metabolic Liver Diseases (CR-GMLD) Group, Beijing, China
| | | | | | | | - Hong You
- Correspondence: E-mail: (Hong You)
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11
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The Utility of Whole Exome Sequencing in Diagnosing Pediatric Neurological Disorders. Balkan J Med Genet 2021; 23:17-24. [PMID: 33816068 PMCID: PMC8009565 DOI: 10.2478/bjmg-2020-0028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Pediatric neurological disorders have a wide spectrum of clinical presentations and can be challenging to diagnose. Whole exome sequencing (WES) is increasingly becoming an integral diagnostic tool in medicine. It is cost-effective and has high diagnostic yield, especially in consanguineous populations. This study aims to review WES results and its value in diagnosing neurological disorders. A retrospective chart review was performed for WES results between the period of January 2018 to November 2019. Whole exome sequencing was requested for children with unexplained neurological signs and symptoms such as epilepsy, developmental delay, visual impairment, spasticity, hypotonia and magnetic resonance imaging (MRI) brain changes. It was conducted for children in a pediatric neurology clinic of a tertiary center at Jeddah, Saudi Arabia. Twenty-six children with undiagnosed neurological conditions were identified and underwent WES diagnosis. Nineteen patients (73.0%) of the cohort were diagnosed with pathogenic variants, likely pathogenic variants or variants of unknown significance (VUS). Consanguinity was positive in 18 families of the cohort (69.0%). Seven patients showed homozygous mutations. Five patients had heterozygous mutations. There were six patients with VUS and six patients had negative WES results. Whole exome sequencing showed a high diagnostic rate in this group of children with variable neurological disorders.
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12
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Kanzi AM, San JE, Chimukangara B, Wilkinson E, Fish M, Ramsuran V, de Oliveira T. Next Generation Sequencing and Bioinformatics Analysis of Family Genetic Inheritance. Front Genet 2020; 11:544162. [PMID: 33193618 PMCID: PMC7649788 DOI: 10.3389/fgene.2020.544162] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 09/21/2020] [Indexed: 12/29/2022] Open
Abstract
Mendelian and complex genetic trait diseases continue to burden and affect society both socially and economically. The lack of effective tests has hampered diagnosis thus, the affected lack proper prognosis. Mendelian diseases are caused by genetic mutations in a singular gene while complex trait diseases are caused by the accumulation of mutations in either linked or unlinked genomic regions. Significant advances have been made in identifying novel diseases associated mutations especially with the introduction of next generation and third generation sequencing. Regardless, some diseases are still without diagnosis as most tests rely on SNP genotyping panels developed from population based genetic analyses. Analysis of family genetic inheritance using whole genomes, whole exomes or a panel of genes has been shown to be effective in identifying disease-causing mutations. In this review, we discuss next generation and third generation sequencing platforms, bioinformatic tools and genetic resources commonly used to analyze family based genomic data with a focus on identifying inherited or novel disease-causing mutations. Additionally, we also highlight the analytical, ethical and regulatory challenges associated with analyzing personal genomes which constitute the data used for family genetic inheritance.
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Affiliation(s)
- Aquillah M. Kanzi
- Kwazulu-Natal Research and Innovation Sequencing Platform (KRISP), School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
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13
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Berardo A, Quinzii CM. Redefining infantile-onset multisystem phenotypes of coenzyme Q 10-deficiency in the next-generation sequencing era. JOURNAL OF TRANSLATIONAL GENETICS AND GENOMICS 2020; 4:22-35. [PMID: 33426503 PMCID: PMC7791541 DOI: 10.20517/jtgg.2020.02] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Primary coenzyme Q10 (CoQ10) deficiency encompasses a subset of mitochondrial diseases caused by mutations affecting proteins involved in the CoQ10 biosynthetic pathway. One of the most frequent clinical syndromes associated with primary CoQ10 deficiency is the severe infantile multisystemic form, which, until recently, was underdiagnosed. In the last few years, the availability of genetic screening through whole exome sequencing and whole genome sequencing has enabled molecular diagnosis in a growing number of patients with this syndrome and has revealed new disease phenotypes and molecular defects in CoQ10 biosynthetic pathway genes. Early genetic screening can rapidly and non-invasively diagnose primary CoQ10 deficiencies. Early diagnosis is particularly important in cases of CoQ10 deficient steroid-resistant nephrotic syndrome, which frequently improves with treatment. In contrast, the infantile multisystemic forms of CoQ10 deficiency, particularly when manifesting with encephalopathy, present therapeutic challenges, due to poor responses to CoQ10 supplementation. Administration of CoQ10 biosynthetic intermediate compounds is a promising alternative to CoQ10; however, further pre-clinical studies are needed to establish their safety and efficacy, as well as to elucidate the mechanism of actions of the intermediates. Here, we review the molecular defects causes of the multisystemic infantile phenotype of primary CoQ10 deficiency, genotype-phenotype correlations, and recent therapeutic advances.
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Affiliation(s)
- Andres Berardo
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA
| | - Catarina M Quinzii
- Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA
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14
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McGrath J, Ohyama M, Simpson M. PADI3
, hair disorders and genomic investigation. Br J Dermatol 2019; 181:1115-1116. [DOI: 10.1111/bjd.18463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J.A. McGrath
- St John's Institute of Dermatology King's College London (Guy's Campus) London U.K
| | - M. Ohyama
- Department of Dermatology Kyorin University Faculty of Medicine Tokyo Japan
| | - M.A. Simpson
- Department of Medical and Molecular Genetics King's College London (Guy's Campus) London U.K
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15
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Li X, Jin Y, Yin Y. Allele frequency of pathogenic variants related to adult-onset Mendelian diseases. Clin Genet 2019; 96:226-235. [PMID: 31119731 DOI: 10.1111/cge.13579] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/16/2019] [Accepted: 05/19/2019] [Indexed: 12/14/2022]
Abstract
An increasing number of variants related to Mendelian diseases have been discovered through analyses of next-generation sequencing data, but the results related to adult-onset Mendelian diseases are insufficient. One possible explanation is that the methods commonly used to evaluate pathogenic variants in patients with congenital Mendelian diseases may not be appropriate for adult-onset diseases due to differences in selection pressure, particularly when assessing the frequency of variants in the general population. We established a well-processed and filtered database of pathogenic variants with both phenotype and frequency information based on the ClinVar and GnomAD public database to better explore the genetic features of adult-onset diseases under real-world conditions. Compared with the control group, pathogenic variants related to adult-onset dominant diseases had a higher allele frequency pattern. Further, the allele frequency patterns of both dominant and recessive variants were higher in patients with neurodegenerative diseases than those in patients with intellectual disabilities. Based on the mutation-selection balance model, the above observation of allele frequency described the lower selection pressure on pathogenic variants related to adult-onset Mendelian diseases and suggests a lower effectiveness of population and loss-of-function evidence in investigations of adult-onset Mendelian diseases.
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Affiliation(s)
- Xiang Li
- Institute of Systems Biomedicine, Department of Pathology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, Peking University Health Science Center, Beijing, China
| | - Yan Jin
- Institute of Systems Biomedicine, Department of Pathology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, Peking University Health Science Center, Beijing, China
| | - Yuxin Yin
- Institute of Systems Biomedicine, Department of Pathology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, Peking University Health Science Center, Beijing, China
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16
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Mu W, Schiess N, Orthmann-Murphy JL, El-Hattab AW. The utility of whole exome sequencing in diagnosing neurological disorders in adults from a highly consanguineous population. J Neurogenet 2019; 33:21-26. [PMID: 30724636 DOI: 10.1080/01677063.2018.1555249] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
There is increasing evidence that whole exome sequencing (WES) has a high diagnostic yield and is cost-efficient for individuals with neurological phenotypes. However, there is limited data on the use of WES in non-Western populations, including populations with a high rate of consanguinity. Retrospective chart review was performed on 24 adults with undiagnosed neurological symptoms evaluated in genetics and neurology clinics in a tertiary care facility on the Arabian Peninsula, and had WES between 2014 and 2016. Definitive diagnoses were made in 13/24 (54%) of cases. Of these, 5/13 (38%) revealed novel pathogenic variants. Of the known 19/24 (79%) consanguineous cases, diagnostic rate was slightly higher, 11/19 (58%) as compared to 2/5 (40%) among non-consanguineous cases. Autosomal recessive disorders comprised 10/13 (77%) of molecular diagnoses, all found to be due to homozygous pathogenic variants among consanguineous cases. WES in this cohort of adults with neurological symptoms had a high diagnostic rate likely due to high consanguinity rates in this population, as evidenced by the high diagnostic rate of homozygous pathogenic variants.
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Affiliation(s)
- Weiyi Mu
- a Institute of Genetic Medicine , Johns Hopkins University , Baltimore , MD , USA
| | - Nicoline Schiess
- b Department of Neurology , Johns Hopkins University , Baltimore , MD , USA
| | - Jennifer L Orthmann-Murphy
- b Department of Neurology , Johns Hopkins University , Baltimore , MD , USA.,c Department of Neurology , Hospital of the University of Pennsylvania , Philadelphia , PA , USA
| | - Ayman W El-Hattab
- d Division of Clinical Genetics and Metabolic Disorder , Tawam Hospital , Al-Ain , United Arab Emirates
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17
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Deal SL, Yamamoto S. Unraveling Novel Mechanisms of Neurodegeneration Through a Large-Scale Forward Genetic Screen in Drosophila. Front Genet 2019; 9:700. [PMID: 30693015 PMCID: PMC6339878 DOI: 10.3389/fgene.2018.00700] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Accepted: 12/13/2018] [Indexed: 01/04/2023] Open
Abstract
Neurodegeneration is characterized by progressive loss of neurons. Genetic and environmental factors both contribute to demise of neurons, leading to diverse devastating cognitive and motor disorders, including Alzheimer's and Parkinson's diseases in humans. Over the past few decades, the fruit fly, Drosophila melanogaster, has become an integral tool to understand the molecular, cellular and genetic mechanisms underlying neurodegeneration. Extensive tools and sophisticated technologies allow Drosophila geneticists to identify and study evolutionarily conserved genes that are essential for neural maintenance. In this review, we will focus on a large-scale mosaic forward genetic screen on the fly X-chromosome that led to the identification of a number of essential genes that exhibit neurodegenerative phenotypes when mutated. Most genes identified from this screen are evolutionarily conserved and many have been linked to human diseases with neurological presentations. Systematic electrophysiological and ultrastructural characterization of mutant tissue in the context of the Drosophila visual system, followed by a series of experiments to understand the mechanism of neurodegeneration in each mutant led to the discovery of novel molecular pathways that are required for neuronal integrity. Defects in mitochondrial function, lipid and iron metabolism, protein trafficking and autophagy are recurrent themes, suggesting that insults that eventually lead to neurodegeneration may converge on a set of evolutionarily conserved cellular processes. Insights from these studies have contributed to our understanding of known neurodegenerative diseases such as Leigh syndrome and Friedreich's ataxia and have also led to the identification of new human diseases. By discovering new genes required for neural maintenance in flies and working with clinicians to identify patients with deleterious variants in the orthologous human genes, Drosophila biologists can play an active role in personalized medicine.
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Affiliation(s)
- Samantha L Deal
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, United States
| | - Shinya Yamamoto
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, United States.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
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18
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Abstract
Tourette syndrome (TS) is a complex disorder characterized by repetitive, sudden, and involuntary movements or vocalizations, called tics. Tics usually appear in childhood, and their severity varies over time. In addition to frequent tics, people with TS are at risk for associated problems including attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety, depression, and problems with sleep. TS occurs in most populations and ethnic groups worldwide, and it is more common in males than in females. Previous family and twin studies have shown that the majority of cases of TS are inherited. TS was previously thought to have an autosomal dominant pattern of inheritance. However, several decades of research have shown that this is unlikely the case. Instead, TS most likely results from a variety of genetic and environmental factors, not changes in a single gene. In the past decade, there has been a rapid development of innovative genetic technologies and methodologies, as well as significant progress in genetic studies of psychiatric disorders. In this review, we will briefly summarize previous genetic epidemiological studies of TS and related disorders. We will also review previous genetic studies based on genome-wide linkage analyses and candidate gene association studies to comment on problems of previous methodological and strategic issues. Our main purpose for this review will be to summarize the new genetic discoveries of TS based on novel genetic methods and strategies, such as genome-wide association studies (GWASs), whole exome sequencing (WES), and whole genome sequencing (WGS). We will also compare the new genetic discoveries of TS with other major psychiatric disorders in order to understand the current status of TS genetics and its relationship with other psychiatric disorders.
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19
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Sadedin SP, Ellis JA, Masters SL, Oshlack A. Ximmer: a system for improving accuracy and consistency of CNV calling from exome data. Gigascience 2018; 7:5091801. [PMID: 30192941 PMCID: PMC6177737 DOI: 10.1093/gigascience/giy112] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 08/23/2018] [Indexed: 01/13/2023] Open
Abstract
Background While exome and targeted next-generation DNA sequencing are primarily used for detecting single nucleotide changes and small indels, detection of copy number variants (CNVs) can provide highly valuable additional information from the data. Although there are dozens of exome CNV detection methods available, these are often difficult to use, and accuracy varies unpredictably between and within datasets. Findings We present Ximmer, a tool that supports an end-to-end process for evaluating, tuning, and running analysis methods for detection of CNVs in germline samples. Ximmer includes a simulation framework, implementations of several commonly used CNV detection methods, and a visualization and curation tool that together enable interactive exploration and quality control of CNV results. Using Ximmer, we comprehensively evaluate CNV detection on four datasets using five different detection methods. We show that application of Ximmer can improve accuracy and aid in quality control of CNV detection results. In addition, Ximmer can be used to run analyses and explore CNV results in exome data. Conclusions Ximmer offers a comprehensive tool and method for applying and improving accuracy of CNV detection methods for exome data.
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Affiliation(s)
- Simon P Sadedin
- Bioinformatics, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia.,Victorian Clinical Genetics Services, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia
| | - Justine A Ellis
- Genes Environment & Complex Disease, Murdoch Children's Research Institute, Royal Children's Hospital Flemington Road, Parkville, Victoria 3052 Australia.,Department of Paediatrics, University of Melbourne, Victoria 3010 Australia.,Centre for Social and Early Emotional Development, Faculty of Health, Deakin University, Burwood, Victoria 3125 Australia
| | - Seth L Masters
- Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Victoria 3052, Australia
| | - Alicia Oshlack
- Bioinformatics, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Road, Parkville, Victoria 3052 Australia.,Department of BioScience, University of Melbourne, Parkville 3050, Australia
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20
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Clavijo RI, Arora H, Gibbs E, Cohen S, Griswold A, Bakircioglu E, Bademci G, Tekin M, Ramasamy R. Whole Exome Sequencing of a Consanguineous Turkish Family Identifies a Mutation in GTF2H3 in Brothers With Spermatogenic Failure. Urology 2018; 120:86-89. [DOI: 10.1016/j.urology.2018.06.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/09/2018] [Accepted: 06/18/2018] [Indexed: 12/30/2022]
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21
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Ewans LJ, Schofield D, Shrestha R, Zhu Y, Gayevskiy V, Ying K, Walsh C, Lee E, Kirk EP, Colley A, Ellaway C, Turner A, Mowat D, Worgan L, Freckmann ML, Lipke M, Sachdev R, Miller D, Field M, Dinger ME, Buckley MF, Cowley MJ, Roscioli T. Whole-exome sequencing reanalysis at 12 months boosts diagnosis and is cost-effective when applied early in Mendelian disorders. Genet Med 2018; 20:1564-1574. [PMID: 29595814 DOI: 10.1038/gim.2018.39] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 01/31/2018] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Whole-exome sequencing (WES) has revolutionized Mendelian diagnostics, however, there is no consensus on the timing of data review in undiagnosed individuals and only preliminary data on the cost-effectiveness of this technology. We aimed to assess the utility of WES data reanalysis for diagnosis in Mendelian disorders and to analyze the cost-effectiveness of this technology compared with a traditional diagnostic pathway. METHODS WES was applied to a cohort of 54 patients from 37 families with a variety of Mendelian disorders to identify the genetic etiology. Reanalysis was performed after 12 months with an improved WES diagnostic pipeline. A comparison was made between costs of a modeled WES pathway and a traditional diagnostic pathway in a cohort with intellectual disability (ID). RESULTS Reanalysis of WES data at 12 months improved diagnostic success from 30 to 41% due to interim publication of disease genes, expanded phenotype data from referrer, and an improved bioinformatics pipeline. Cost analysis on the ID cohort showed average cost savings of US$586 (AU$782) for each additional diagnosis. CONCLUSION Early application of WES in Mendelian disorders is cost-effective and reanalysis of an undiagnosed individual at a 12-month time point increases total diagnoses by 11%.
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Affiliation(s)
- Lisa J Ewans
- St Vincent's Clinical School, University of New South Wales, Darlinghurst, New South Wales, Australia. .,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.
| | - Deborah Schofield
- Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,Faculty of Pharmacy, Charles Perkins Centre, University of Sydney, Sydney, New South Wales, Australia.,Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Rupendra Shrestha
- Faculty of Pharmacy, Charles Perkins Centre, University of Sydney, Sydney, New South Wales, Australia
| | - Ying Zhu
- The Genetics of Learning Disability Service, Waratah, New South Wales, Australia.,Randwick Genetics, NSW Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Velimir Gayevskiy
- Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Kevin Ying
- Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Corrina Walsh
- Randwick Genetics, NSW Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Eric Lee
- Randwick Genetics, NSW Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Edwin P Kirk
- Randwick Genetics, NSW Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Sydney, New South Wales, Australia
| | - Alison Colley
- Clinical Genetics Department, Liverpool Hospital, Liverpool, New South Wales, Australia
| | - Carolyn Ellaway
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,Disciplines of Child and Adolescent Health and Genetic Medicine, University of Sydney, New South Wales, Australia
| | - Anne Turner
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Sydney, New South Wales, Australia
| | - David Mowat
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Sydney, New South Wales, Australia
| | - Lisa Worgan
- Clinical Genetics Department, Liverpool Hospital, Liverpool, New South Wales, Australia
| | - Mary-Louise Freckmann
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Sydney, New South Wales, Australia
| | - Michelle Lipke
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,Lady Cilento Children's Hospital, Brisbane, Queensland, Australia
| | - Rani Sachdev
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Sydney, New South Wales, Australia
| | - David Miller
- Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Michael Field
- The Genetics of Learning Disability Service, Waratah, New South Wales, Australia
| | - Marcel E Dinger
- St Vincent's Clinical School, University of New South Wales, Darlinghurst, New South Wales, Australia.,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Michael F Buckley
- Randwick Genetics, NSW Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Mark J Cowley
- St Vincent's Clinical School, University of New South Wales, Darlinghurst, New South Wales, Australia.,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Tony Roscioli
- Randwick Genetics, NSW Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,NeuRA and Prince of Wales Clinical School, University of New South Wales, Kensington, Australia, New South Wales
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22
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Fadista J, Oskolkov N, Hansson O, Groop L. LoFtool: a gene intolerance score based on loss-of-function variants in 60 706 individuals. Bioinformatics 2017; 33:471-474. [PMID: 27563026 DOI: 10.1093/bioinformatics/btv602] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 10/13/2015] [Indexed: 11/13/2022] Open
Abstract
Motivation Depletion of loss-of-function (LoF) mutations may provide a rank of genic functional intolerance and consequently susceptibility to disease. Results Here we have studied LoF mutations in 60 706 unrelated individuals and show that the most intolerant quartile of ranked genes is enriched in rare and early onset diseases and explains 87% of de novo haploinsufficient OMIM mutations, 17% more than any other gene scoring tool. We detected particular enrichment in expression of the depleted LoF genes in brain (odds ratio = 1.5; P -value = 4.2e-07). By searching for de novo haploinsufficient mutations putatively associated with neurodevelopmental disorders in four recent studies, we were able to explain 81% of them. Taken together, this study provides a novel gene intolerance ranking system, called LoFtool, which may help in ranking genes of interest based on their LoF intolerance and tissue expression. Availability and implementation The LoFtool gene scores are available in the Supplementary data . Contact joaofadista@gmail.com. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- João Fadista
- Department of Epidemiology Research, Statens Serum Institut, 2300 Copenhagen S, Denmark.,Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Sweden and
| | - Nikolay Oskolkov
- Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Sweden and
| | - Ola Hansson
- Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Sweden and
| | - Leif Groop
- Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Sweden and.,Institute for Molecular Medicine Finland FIMM, University of Helsinki, Helsinki, Finland
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23
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Qi Y, Zheng Y, Li Z, Xiong L. Progress in Genetic Studies of Tourette's Syndrome. Brain Sci 2017; 7:E134. [PMID: 29053637 PMCID: PMC5664061 DOI: 10.3390/brainsci7100134] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/03/2017] [Accepted: 10/17/2017] [Indexed: 12/23/2022] Open
Abstract
Tourette's Syndrome (TS) is a complex disorder characterized by repetitive, sudden, and involuntary movements or vocalizations, called tics. Tics usually appear in childhood, and their severity varies over time. In addition to frequent tics, people with TS are at risk for associated problems including attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety, depression, and problems with sleep. TS occurs in most populations and ethnic groups worldwide, and it is more common in males than in females. Previous family and twin studies have shown that the majority of cases of TS are inherited. TS was previously thought to have an autosomal dominant pattern of inheritance. However, several decades of research have shown that this is unlikely the case. Instead TS most likely results from a variety of genetic and environmental factors, not changes in a single gene. In the past decade, there has been a rapid development of innovative genetic technologies and methodologies, as well as significant progresses in genetic studies of psychiatric disorders. In this review, we will briefly summarize previous genetic epidemiological studies of TS and related disorders. We will also review previous genetic studies based on genome-wide linkage analyses and candidate gene association studies to comment on problems of previous methodological and strategic issues. Our main purpose for this review will be to summarize the new genetic discoveries of TS based on novel genetic methods and strategies, such as genome-wide association studies (GWASs), whole exome sequencing (WES) and whole genome sequencing (WGS). We will also compare the new genetic discoveries of TS with other major psychiatric disorders in order to understand the current status of TS genetics and its relationship with other psychiatric disorders.
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Affiliation(s)
- Yanjie Qi
- Laboratoire de Neurogénétique, Centre de Recherche, Institut Universitaire en Santé Mentale de Montréal, Montreal, QC H1N 3V2, Canada.
- Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100088, China.
| | - Yi Zheng
- Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100088, China.
- Center of Schizophrenia, Beijing Institute for Brain Disorders, Beijing 100088, China.
| | - Zhanjiang Li
- Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100088, China.
- Center of Schizophrenia, Beijing Institute for Brain Disorders, Beijing 100088, China.
| | - Lan Xiong
- Laboratoire de Neurogénétique, Centre de Recherche, Institut Universitaire en Santé Mentale de Montréal, Montreal, QC H1N 3V2, Canada.
- Département de Psychiatrie, Faculté de Médecine, Université de Montréal, Montreal, QC H3C 3J7, Canada.
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC H3A 2B4, Canada.
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Altmüller J, Motameny S, Becker C, Thiele H, Chatterjee S, Wollnik B, Nürnberg P. A systematic comparison of two new releases of exome sequencing products: the aim of use determines the choice of product. Biol Chem 2017; 397:791-801. [PMID: 27021259 DOI: 10.1515/hsz-2015-0300] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/16/2016] [Indexed: 11/15/2022]
Abstract
We received early access to the newest releases of exome sequencing products, namely Agilent SureSelect v6 (Agilent, Santa Clara, CA, USA) and NimbleGen MedExome (Roche NimbleGen, Basel, Switzerland), and we conducted whole exome sequencing (WES) of several DNA samples with each of these products in order to assess their performance. Here, we provide a detailed evaluation of the original, normalized (with respect to the different target sizes), and trimmed data sets and compare them in terms of the amount of duplicates, the reads on target, and the enrichment evenness. In addition to these general statistics, we performed a detailed analysis of the frequently mutated and newly described genes found in 'The Deciphering Developmental Disorders Study' published very recently (Fitzgerald, T.W., Gerety, S.S., Jones, W.D., van Kogelenberg, M., King, D.A., McRae, J., Morley, K.I., Parthiban, V., Al-Turki, S., Ambridge, K., et al. (2015). Large-scale discovery of novel genetic causes of developmental disorders. Nature 519, 223-228.). In our comparison, the Agilent v6 exome performs better than the NimbleGen's MedExome both in terms of efficiency and evenness of coverage distribution. With its larger target size, it is also more comprehensive, and therefore the better choice in research projects that aim to identify novel disease-associated genes. In contrast, if the exomes are mainly used in a diagnostic setting, we see advantages for the new NimbleGen MedExome. We find a superior coverage here in those genes of high clinical relevance that likely allows for a better detection of relevant, disease-causing mutations.
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Whole-exome sequencing identifies a novel de novo mutation in DYNC1H1 in epileptic encephalopathies. Sci Rep 2017; 7:258. [PMID: 28325891 PMCID: PMC5428060 DOI: 10.1038/s41598-017-00208-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/14/2017] [Indexed: 11/23/2022] Open
Abstract
Epileptic encephalopathies (EE) are a group of severe childhood epilepsy disorders characterized by intractable seizures, cognitive impairment and neurological deficits. Recent whole-exome sequencing (WES) studies have implicated significant contribution of de novo mutations to EE. In this study, we utilized WES for identifying causal de novo mutations in 4 parent-offspring trios affected by West syndrome. As a result, we found two deleterious de novo mutations in DYNC1H1 and RTP1 in two trios. Expression profile analysis showed that DYNC1H1 and RTP1 are expressed in almost all brain regions and developmental stages. Interestingly, co-expression and genetic interaction network analyses suggested that DYNC1H1 and RTP1 are tightly associated with known epilepsy genes. Furthermore, we observed that the de novo mutations of DYNC1H1 were identified in several different neuropsychiatric disorders including EE, autism spectrum disorders and intellectual disabilities by previous studies, and these mutations primarily occurred in the functional domain of the protein. Taken together, these results demonstrate DYNC1H1 as a strong candidate and RTP1 as a potential candidate on the onset of EE. In addition, this work also proves WES as a powerful tool for the molecular genetic dissection of children affected by sporadic EE.
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Ku CS, Cooper DN, Patrinos GP. The Rise and Rise of Exome Sequencing. Public Health Genomics 2016; 19:315-324. [DOI: 10.1159/000450991] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 09/23/2016] [Indexed: 12/19/2022] Open
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Lopez-Escamez JA, Bibas T, Cima RFF, Van de Heyning P, Knipper M, Mazurek B, Szczepek AJ, Cederroth CR. Genetics of Tinnitus: An Emerging Area for Molecular Diagnosis and Drug Development. Front Neurosci 2016; 10:377. [PMID: 27594824 PMCID: PMC4990555 DOI: 10.3389/fnins.2016.00377] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 08/03/2016] [Indexed: 12/13/2022] Open
Abstract
Subjective tinnitus is the perception of sound in the absence of external or bodily-generated sounds. Chronic tinnitus is a highly prevalent condition affecting over 70 million people in Europe. A wide variety of comorbidities, including hearing loss, psychiatric disorders, neurodegenerative disorders, and temporomandibular joint (TMJ) dysfunction, have been suggested to contribute to the onset or progression of tinnitus; however, the precise molecular mechanisms of tinnitus are not well understood and the contribution of genetic and epigenetic factors remains unknown. Human genetic studies could enable the identification of novel molecular therapeutic targets, possibly leading to the development of novel pharmaceutical therapeutics. In this article, we briefly discuss the available evidence for a role of genetics in tinnitus and consider potential hurdles in designing genetic studies for tinnitus. Since multiple diseases have tinnitus as a symptom and the supporting genetic evidence is sparse, we propose various strategies to investigate the genetic underpinnings of tinnitus, first by showing evidence of heritability using concordance studies in twins, and second by improving patient selection according to phenotype and/or etiology in order to control potential biases and optimize genetic data output. The increased knowledge resulting from this endeavor could ultimately improve the drug development process and lead to the preventive or curative treatment of tinnitus.
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Affiliation(s)
- Jose A Lopez-Escamez
- Otology and Neurotology Group, Department of Genomic Medicine, Pfizer - Universidad de Granada - Junta de Andalucía Centro de Genómica e Investigación Oncológica, PTSGranada, Spain; Department of Otolaryngology, Instituto de Investigación Biosanitaria ibs.GRANADA, Complejo Hospital Universitario GranadaGranada, Spain
| | - Thanos Bibas
- 1st Department of Otolaryngology, National and Kapodistrian University of Athens, Hippocrateion HospitalAthens, Greece; Ear Institute, UCLLondon, UK
| | - Rilana F F Cima
- Department of Clinical Psychological Science, Maastricht University Maastricht, Netherlands
| | - Paul Van de Heyning
- University Department ENT and Head and Neck Surgery, Antwerp University Hospital, University of Antwerp Antwerp, Belgium
| | - Marlies Knipper
- Hearing Research Centre Tübingen, Molecular Physiology of Hearing Tübingen, Germany
| | - Birgit Mazurek
- Tinnitus Center, Charité-Universitätsmedizin Berlin Berlin, Germany
| | | | - Christopher R Cederroth
- Experimental Audiology, Department of Physiology and Pharmacology, Karolinska Institutet Stockholm, Sweden
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28
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Sener EF, Canatan H, Ozkul Y. Recent Advances in Autism Spectrum Disorders: Applications of Whole Exome Sequencing Technology. Psychiatry Investig 2016; 13:255-64. [PMID: 27247591 PMCID: PMC4878959 DOI: 10.4306/pi.2016.13.3.255] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 09/22/2015] [Accepted: 10/02/2015] [Indexed: 02/07/2023] Open
Abstract
Autism spectrum disorders (ASD) is characterized by three core symptoms with impaired reciprocal social interaction and communication, a pattern of repetitive behavior and/or restricted interests in early childhood. The prevalence is higher in male children than in female children. As a complex neurodevelopmental disorder, the phenotype and severity of autism are extremely heterogeneous with differences from one patient to another. Genetics has a key role in the etiology of autism. Environmental factors are also interacting with the genetic profile and cause abnormal changes in neuronal development, brain growth, and functional connectivity. The term of exome represents less than 1% of the human genome, but contains 85% of known disease-causing variants. Whole-exome sequencing (WES) is an application of the next generation sequencing technology to determine the variations of all coding regions, or exons of known genes. For this reason, WES has been extensively used for clinical studies in the recent years. WES has achieved great success in the past years for identifying Mendelian disease genes. This review evaluates the potential of current findings in ASD for application in next generation sequencing technology, particularly WES. WES and whole-genome sequencing (WGS) approaches may lead to the discovery of underlying genetic factors for ASD and may thereby identify novel therapeutic targets for this disorder.
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Affiliation(s)
- Elif Funda Sener
- Department of Medical Biology, Erciyes University Medical Faculty, Kayseri, Turkey
- Erciyes University Genome and Stem Cell Center, Kayseri, Turkey
| | - Halit Canatan
- Department of Medical Biology, Erciyes University Medical Faculty, Kayseri, Turkey
| | - Yusuf Ozkul
- Department of Medical Genetics, Erciyes University Medical Faculty, Kayseri, Turkey
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Higuchi Y, Hashiguchi A, Yuan J, Yoshimura A, Mitsui J, Ishiura H, Tanaka M, Ishihara S, Tanabe H, Nozuma S, Okamoto Y, Matsuura E, Ohkubo R, Inamizu S, Shiraishi W, Yamasaki R, Ohyagi Y, Kira JI, Oya Y, Yabe H, Nishikawa N, Tobisawa S, Matsuda N, Masuda M, Kugimoto C, Fukushima K, Yano S, Yoshimura J, Doi K, Nakagawa M, Morishita S, Tsuji S, Takashima H. Mutations in MME cause an autosomal-recessive Charcot-Marie-Tooth disease type 2. Ann Neurol 2016; 79:659-72. [PMID: 26991897 PMCID: PMC5069600 DOI: 10.1002/ana.24612] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/16/2016] [Accepted: 02/03/2016] [Indexed: 01/12/2023]
Abstract
Objective The objective of this study was to identify new causes of Charcot–Marie–Tooth (CMT) disease in patients with autosomal‐recessive (AR) CMT. Methods To efficiently identify novel causative genes for AR‐CMT, we analyzed 303 unrelated Japanese patients with CMT using whole‐exome sequencing and extracted recessive variants/genes shared among multiple patients. We performed mutation screening of the newly identified membrane metalloendopeptidase (MME) gene in 354 additional patients with CMT. We clinically, genetically, pathologically, and radiologically examined 10 patients with the MME mutation. Results We identified recessive mutations in MME in 10 patients. The MME gene encodes neprilysin (NEP), which is well known to be one of the most prominent beta‐amyloid (Aβ)‐degrading enzymes. All patients had a similar phenotype consistent with late‐onset axonal neuropathy. They showed muscle weakness, atrophy, and sensory disturbance in the lower extremities. All the MME mutations could be loss‐of‐function mutations, and we confirmed a lack/decrease of NEP protein expression in a peripheral nerve. No patients showed symptoms of dementia, and 1 patient showed no excess Aβ in Pittsburgh compound‐B positron emission tomography imaging. Interpretation Our results indicate that loss‐of‐function MME mutations are the most frequent cause of adult‐onset AR‐CMT2 in Japan, and we propose that this new disease should be termed AR‐CMT2T. A loss‐of‐function MME mutation did not cause early‐onset Alzheimer's disease. Identifying the MME mutation responsible for AR‐CMT could improve the rate of molecular diagnosis and the understanding of the molecular mechanisms of CMT. Ann Neurol 2016;79:659–672
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Affiliation(s)
- Yujiro Higuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Junhui Yuan
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Jun Mitsui
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroyuki Ishiura
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Masaki Tanaka
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Satoshi Ishihara
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.,Department of Cardiovascular medicine, Nephrology and Neurology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Hajime Tanabe
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Satoshi Nozuma
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Eiji Matsuura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Ryuichi Ohkubo
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.,Department of Neurology, Fujimoto General Hospital, Miyazaki, Japan
| | - Saeko Inamizu
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Wataru Shiraishi
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Ryo Yamasaki
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yasumasa Ohyagi
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Jun-ichi Kira
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yasushi Oya
- Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Hayato Yabe
- Department of Neurology and Clinical Pharmacology, Ehime University Graduate School of Medicine, Ehime, Japan
| | - Noriko Nishikawa
- Department of Neurology and Clinical Pharmacology, Ehime University Graduate School of Medicine, Ehime, Japan
| | - Shinsuke Tobisawa
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Nozomu Matsuda
- Department of Neurology, Fukushima Medical University, Fukushima, Japan
| | - Masayuki Masuda
- Department of Neurology, Tokyo Medical University, Tokyo, Japan
| | - Chiharu Kugimoto
- Department of Neurology and Stroke Medicine, Yokohama City University, Yokohama, Japan
| | - Kazuhiro Fukushima
- Department of Home-Care Promotion, Shinshu University School of Medicine, Matsumoto, Japan
| | - Satoshi Yano
- Department of Neurology, Showa University School of Medicine, Tokyo, Japan
| | - Jun Yoshimura
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Koichiro Doi
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Masanori Nakagawa
- Director of North Medical Center, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Shinichi Morishita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan
| | - Shoji Tsuji
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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30
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Souzeau E, Burdon KP, Mackey DA, Hewitt AW, Savarirayan R, Otlowski M, Craig JE. Ethical Considerations for the Return of Incidental Findings in Ophthalmic Genomic Research. Transl Vis Sci Technol 2016; 5:3. [PMID: 26929883 PMCID: PMC4757467 DOI: 10.1167/tvst.5.1.3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 11/02/2015] [Indexed: 12/25/2022] Open
Abstract
Whole genome and whole exome sequencing technologies are being increasingly used in research. However, they have the potential to identify incidental findings (IF), findings not related to the indication of the test, raising questions regarding researchers' responsibilities toward the return of this information to participants. In this study we discuss the ethical considerations related to the return of IF to research participants, emphasizing that the type of the study matters and describing the current practice standards. There are currently no legal obligations for researchers to return IF to participants, but some viewpoints consider that researchers might have an ethical one to return IF of clinical validity and clinical utility and that are actionable. The reality is that most IF are complex to interpret, especially since they were not the indication of the test. The clinical utility often depends on the participants' preferences, which can be challenging to conciliate and relies on participants' understanding. In summary, in the context of a lack of clear guidance, researchers need to have a clear plan for the disclosure or nondisclosure of IF from genomic research, balancing their research goals and resources with the participants' rights and their duty not to harm.
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Affiliation(s)
- Emmanuelle Souzeau
- Department of Ophthalmology Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Kathryn P. Burdon
- Department of Ophthalmology Flinders University, Flinders Medical Centre, Adelaide, Australia
- Menzies Institute of Medical Research, University of Tasmania, Hobart, Australia
| | - David A. Mackey
- Menzies Institute of Medical Research, University of Tasmania, Hobart, Australia
- Centre for Ophthalmology and Visual Science, Lions Eye Institute, University of Western Australia, Perth, Australia
| | - Alex W. Hewitt
- Menzies Institute of Medical Research, University of Tasmania, Hobart, Australia
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Ravi Savarirayan
- Victorian Clinical Genetics Service, Murdoch Childrens Research Institute, University of Melbourne, Melbourne, Australia
| | | | - Jamie E. Craig
- Department of Ophthalmology Flinders University, Flinders Medical Centre, Adelaide, Australia
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31
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Cherukuri PF, Maduro V, Fuentes-Fajardo KV, Lam K, Adams DR, Tifft CJ, Mullikin JC, Gahl WA, Boerkoel CF. Replicate exome-sequencing in a multiple-generation family: improved interpretation of next-generation sequencing data. BMC Genomics 2015; 16:998. [PMID: 26602380 PMCID: PMC4659195 DOI: 10.1186/s12864-015-2107-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 10/16/2015] [Indexed: 12/18/2022] Open
Abstract
Background Whole-exome sequencing (WES) is rapidly evolving into a tool of choice for rapid, and inexpensive identification of molecular genetic lesions within targeted regions of the human genome. While biases in WES coverage of nucleotides in targeted regions are recognized, it is not well understood how repetition of WES improves the interpretation of sequencing results in a clinical diagnostic setting. Method To address this, we compared independently generated exome-capture of six individuals from three-generations sequenced in triplicate. This generated between 48x-86x mean target depth of high-quality mapped bases (>Q20) for each technical replicate library. Cumulatively, we achieved 179 - 208x average target coverage for each individual in the pedigree. Using this experimental design, we evaluated stochastics in WES interpretation, genotyping sensitivity, and accuracy to detect de novo variants. Results In this study, we show that repetition of WES improved the interpretation of the capture target regions after aggregating the data (93.5 - 93.9 %). Compared to 81.2 - 89.6 % (50.2-55.4 Mb of 61.7 M) coverage of targeted bases at ≥20x in the individual technical replicates, the aggregated data covered 93.5 - 93.9 % of targeted bases (57.7 – 58.0 of 61.7 M) at ≥20x threshold, suggesting a 4.3 – 12.7 % improvement in coverage. Each individual’s aggregate dataset recovered 3.4 – 6.4 million bases within variable targeted regions. We uncovered technical variability (2-5 %) inherent to WES technique. We also show improved interpretation in assessing clinically important regions that lack interpretation under current conditions, affecting 12–16 of the 56 genes recommended for secondary analysis by American College of Medical Genetics (ACMG). We demonstrate that comparing technical replicate WES datasets and their derived aggregate data can effectively address overall WES genotyping discrepancies. Conclusion We describe a method to evaluate the reproducibility and stochastics in exome library preparation, and delineate the advantages of aggregating the data derived from technical replicates. The implications of this study are directly applicable to improved experimental design and provide an opportunity to rapidly, efficiently, and accurately arrive at reliable candidate nucleotide variants. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2107-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Praveen F Cherukuri
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA. .,Inova Translational Medicine Institute, Inova Health System, Falls Church, VA, USA.
| | - Valerie Maduro
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA.
| | - Karin V Fuentes-Fajardo
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA.
| | - Kevin Lam
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA.
| | | | - David R Adams
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA. .,Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA.
| | - Cynthia J Tifft
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA. .,Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA.
| | - James C Mullikin
- NIH Intramural Sequencing Center, National Human Genome Research Institute, NIH, Bethesda, MD, USA.
| | - William A Gahl
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA. .,Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, MD, USA.
| | - Cornelius F Boerkoel
- NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA.
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Abstract
Approximately 50% of all congenital anomalies cannot be linked to any specific genetic etiology, but in recent years cost effective high throughput sequencing has emerged as an efficient strategy for identifying single nucleotide polymorphisms (SNPs) associated with disease. However, in many cases there is not enough evidence to determine if these SNPs underlie disease. To bridge this gap in our understanding advances in functional analyses are warranted. Several preclinical model systems are currently being utilized to provide such evidence, including the advantageous zebrafish embryo. While every system exhibits disadvantages and caveats, a new era of multidisciplinary research has evolved, which uses a broad spectrum of functional analysis tools. This approach will make it possible to identify potential therapeutic targets for both common and rare human disorders.
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Affiliation(s)
- Anita M Quintana
- Department of Biological Sciences, The University of Texas at El Paso, 500 West University Avenue, El Paso TX 79934
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33
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Abstract
With the rapid development of readily accessible molecular diagnostic tools, a growing number of patients and families with craniofacial anomalies will have access to a confirmed molecular diagnosis. This chapter provides an overview to current clinical and molecular resources and approaches used by diagnostician today. Clarifying the underlying cause of a congenital defect is necessary to provide proper counseling, identify carrier/risk status of family members, inform prognosis and direct appropriate management, treatments, and surveillance recommendations. The use of molecular testing has evolved to confirm a suspected clinical diagnosis, establish a diagnosis in an unclear condition and end a diagnostic odyssey for many children with underlying syndromes, but the use of these techniques to understand common nonsyndromic malformations like clefts and craniosynostosis is still an active area of research that will contribute to clinical care in the future.
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34
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A Novel C-Terminal CIB2 (Calcium and Integrin Binding Protein 2) Mutation Associated with Non-Syndromic Hearing Loss in a Hispanic Family. PLoS One 2015; 10:e0133082. [PMID: 26426422 PMCID: PMC4591343 DOI: 10.1371/journal.pone.0133082] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 06/22/2015] [Indexed: 01/29/2023] Open
Abstract
Hearing loss is a complex disorder caused by both genetic and environmental factors. Previously, mutations in CIB2 have been identified as a common cause of genetic hearing loss in Pakistani and Turkish populations. Here we report a novel (c.556C>T; p.(Arg186Trp)) transition mutation in the CIB2 gene identified through whole exome sequencing (WES) in a Caribbean Hispanic family with non-syndromic hearing loss. CIB2 belongs to the family of calcium-and integrin-binding (CIB) proteins. The carboxy-termini of CIB proteins are associated with calcium binding and intracellular signaling. The p.(Arg186Trp) mutation is localized within predicted type II PDZ binding ligand at the carboxy terminus. Our ex vivo studies revealed that the mutation did not alter the interactions of CIB2 with Whirlin, nor its targeting to the tips of hair cell stereocilia. However, we found that the mutation disrupts inhibition of ATP-induced Ca2+ responses by CIB2 in a heterologous expression system. Our findings support p.(Arg186Trp) mutation as a cause for hearing loss in this Hispanic family. In addition, it further highlights the necessity of the calcium binding property of CIB2 for normal hearing.
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35
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Sokolenko AP, Suspitsin EN, Kuligina ES, Bizin IV, Frishman D, Imyanitov EN. Identification of novel hereditary cancer genes by whole exome sequencing. Cancer Lett 2015; 369:274-88. [PMID: 26427841 DOI: 10.1016/j.canlet.2015.09.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/23/2015] [Accepted: 09/23/2015] [Indexed: 02/09/2023]
Abstract
Whole exome sequencing (WES) provides a powerful tool for medical genetic research. Several dozens of WES studies involving patients with hereditary cancer syndromes have already been reported. WES led to breakthrough in understanding of the genetic basis of some exceptionally rare syndromes; for example, identification of germ-line SMARCA4 mutations in patients with ovarian hypercalcemic small cell carcinomas indeed explains a noticeable share of familial aggregation of this disease. However, studies on common cancer types turned out to be more difficult. In particular, there is almost a dozen of reports describing WES analysis of breast cancer patients, but none of them yet succeeded to reveal a gene responsible for the significant share of missing heritability. Virtually all components of WES studies require substantial improvement, e.g. technical performance of WES, interpretation of WES results, mode of patient selection, etc. Most of contemporary investigations focus on genes with autosomal dominant mechanism of inheritance; however, recessive and oligogenic models of transmission of cancer susceptibility also need to be considered. It is expected that the list of medically relevant tumor-predisposing genes will be rapidly expanding in the next few years.
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Affiliation(s)
- Anna P Sokolenko
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, St.-Petersburg 197758, Russia; Department of Medical Genetics, St.-Petersburg Pediatric Medical University, St.-Petersburg 194100, Russia
| | - Evgeny N Suspitsin
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, St.-Petersburg 197758, Russia; Department of Medical Genetics, St.-Petersburg Pediatric Medical University, St.-Petersburg 194100, Russia
| | - Ekatherina Sh Kuligina
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, St.-Petersburg 197758, Russia
| | - Ilya V Bizin
- Laboratory of Bioinformatics, RASA Research Center, St.-Petersburg State Polytechnical University, St.-Petersburg 195251, Russia
| | - Dmitrij Frishman
- Department of Bioinformatics, Wissenschaftszentrum Weihenstephan, TU Muenchen, Freising 85354, Germany; Helmholtz Center Munich - German Research Center for Environmental Health (GmbH), Institute of Bioinformatics and Systems Biology, Neuherberg 85764, Germany
| | - Evgeny N Imyanitov
- Department of Tumor Growth Biology, N.N. Petrov Institute of Oncology, St.-Petersburg 197758, Russia; Department of Medical Genetics, St.-Petersburg Pediatric Medical University, St.-Petersburg 194100, Russia; Department of Oncology, I.I. Mechnikov North-Western Medical University, St.-Petersburg 191015, Russia; Department of Oncology, St.-Petersburg State University, St.-Petersburg 199034, Russia.
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Ashton-Prolla P, Goldim JR, Vairo FPE, da Silveira Matte U, Sequeiros J. Genomic analysis in the clinic: benefits and challenges for health care professionals and patients in Brazil. J Community Genet 2015; 6:275-83. [PMID: 26040235 PMCID: PMC4524873 DOI: 10.1007/s12687-015-0238-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 05/13/2015] [Indexed: 12/20/2022] Open
Abstract
Despite significant advances in the diagnosis and treatment of genetic diseases in the last two decades, there is still a significant proportion where a causative mutation cannot be identified and a definitive genetic diagnosis remains elusive. New genome-wide or high-throughput multiple gene tests have brought new hope to the field, since they can offer fast, cost-effective and comprehensive analysis of genetic variation. This is particularly interesting in disorders with high genetic heterogeneity. There are, however, limitations and concerns regarding the implementation of genomic analysis in everyday clinical practice, including some particular to emerging and developing economies, as Brazil. They include the limited number of actionable genetic variants known to date, difficulties in determining the clinical validity and utility of novel variants, growth of direct-to-consumer genetic testing using a genomic approach and lack of proper training of health care professionals to adequately request, interpret and use genetic information. Despite all these concerns and limitations, the availability of genomic tests has grown at an extremely rapid pace and commercially available services include initiatives in almost all areas of clinical genetics, including newborn and carrier screening. We discuss the benefits and limitations of genomic testing, as well as the ethical implications and the challenges for genetic education and enough available and qualified health care professionals, to ensure the adequate process of informed consent, meaningful interpretation and use of genomic data and definition of a clear regulatory framework in the particular context of Brazil.
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Affiliation(s)
- Patrícia Ashton-Prolla
- Serviço de Genetica Medica, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil,
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Marfany G, Gonzàlez-Duarte R. Clinical applications of high-throughput genetic diagnosis in inherited retinal dystrophies: Present challenges and future directions. World J Med Genet 2015; 5:14-22. [DOI: 10.5496/wjmg.v5.i2.14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 12/30/2014] [Accepted: 02/09/2015] [Indexed: 02/06/2023] Open
Abstract
The advent of next generation sequencing (NGS) techniques has greatly simplified the molecular diagnosis and gene identification in very rare and highly heterogeneous Mendelian disorders. Over the last two years, these approaches, especially whole exome sequencing (WES), alone or combined with homozygosity mapping and linkage analysis, have proved to be successful in the identification of more than 25 new causative retinal dystrophy genes. NGS-approaches have also identified a wealth of new mutations in previously reported genes and have provided more comprehensive information concerning the landscape of genotype-phenotype correlations and the genetic complexity/diversity of human control populations. Although whole genome sequencing is far more informative than WES, the functional meaning of the genetic variants identified by the latter can be more easily interpreted, and final diagnosis of inherited retinal dystrophies is extremely successful, reaching 80%, particularly for recessive cases. Even considering the present limitations of WES, the reductions in costs and time, the continual technical improvements, the implementation of refined bioinformatic tools and the unbiased comprehensive genetic information it provides, make WES a very promising diagnostic tool for routine clinical and genetic diagnosis in the future.
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Tetreault M, Bareke E, Nadaf J, Alirezaie N, Majewski J. Whole-exome sequencing as a diagnostic tool: current challenges and future opportunities. Expert Rev Mol Diagn 2015; 15:749-60. [PMID: 25959410 DOI: 10.1586/14737159.2015.1039516] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Whole-exome sequencing (WES) represents a significant breakthrough in the field of human genetics. This technology has largely contributed to the identification of new disease-causing genes and is now entering clinical laboratories. WES represents a powerful tool for diagnosis and could reduce the 'diagnostic odyssey' for many patients. In this review, we present a technical overview of WES analysis, variants annotation and interpretation in a clinical setting. We evaluate the usefulness of clinical WES in different clinical indications, such as rare diseases, cancer and complex diseases. Finally, we discuss the efficacy of WES as a diagnostic tool and the impact on patient management.
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Affiliation(s)
- Martine Tetreault
- Department of Human Genetics, McGill University, Montreal, QC H3A 1B1, Canada
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A combination of targeted enrichment methodologies for whole-exome sequencing reveals novel pathogenic mutations. Sci Rep 2015; 5:9331. [PMID: 25786579 PMCID: PMC4365396 DOI: 10.1038/srep09331] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 03/02/2015] [Indexed: 12/13/2022] Open
Abstract
Whole-exome sequencing (WES) is a useful method to identify disease-causing mutations, however, often no candidate mutations are identified using commonly available targeted probe sets. In a recent analysis, we also could not find candidate mutations for 20.9% (9/43) of our pedigrees with congenital neurological disorder using pre-designed capture probes (SureSelect V4 or V5). One possible cause for this lack of candidates is that standard WES cannot sequence all protein-coding sequences (CDS) due to capture probe design and regions of low coverage, which account for approximately 10% of all CDS regions. In this study, we combined a selective circularization-based target enrichment method (HaloPlex) with a hybrid capture method (SureSelect V5; WES), and achieved a more complete coverage of CDS regions (~97% of all CDS). We applied this approach to 7 (SureSelect V5) out of 9 pedigrees with no candidates through standard WES analysis and identified novel pathogenic mutations in one pedigree. The application of this effective combination of targeted enrichment methodologies can be expected to aid in the identification of novel pathogenic mutations previously missed by standard WES analysis.
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40
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Requena T, Cabrera S, Martín-Sierra C, Price SD, Lysakowski A, Lopez-Escamez JA. Identification of two novel mutations in FAM136A and DTNA genes in autosomal-dominant familial Meniere's disease. Hum Mol Genet 2014; 24:1119-26. [PMID: 25305078 DOI: 10.1093/hmg/ddu524] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Meniere's disease (MD) is a chronic disorder of the inner ear defined by sensorineural hearing loss, tinnitus and episodic vertigo, and familial MD is observed in 5-15% of sporadic cases. Although its pathophysiology is largely unknown, studies in human temporal bones have found an accumulation of endolymph in the scala media of the cochlea. By whole-exome sequencing, we have identified two novel heterozygous single-nucleotide variants in FAM136A and DTNA genes, both in a Spanish family with three affected cases in consecutive generations, highly suggestive of autosomal-dominant inheritance. The nonsense mutation in the FAM136A gene leads to a stop codon that disrupts the FAM136A protein product. Sequencing revealed two mRNA transcripts of FAM136A in lymphoblasts from patients, which were confirmed by immunoblotting. Carriers of the FAM136A mutation showed a significant decrease in the expression level of both transcripts in lymphoblastoid cell lines. The missense mutation in the DTNA gene produces a novel splice site which skips exon 21 and leads to a shorter alternative transcript. We also demonstrated that FAM136A and DTNA proteins are expressed in the neurosensorial epithelium of the crista ampullaris of the rat by immunohistochemistry. While FAM136A encodes a mitochondrial protein with unknown function, DTNA encodes a cytoskeleton-interacting membrane protein involved in the formation and stability of synapses with a crucial role in the permeability of the blood-brain barrier. Neither of these genes has been described in patients with hearing loss, FAM136A and DTNA being candidate gene for familiar MD.
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Affiliation(s)
- Teresa Requena
- Otology & Neurotology Group CTS495, Department of Genomic Medicine, GENYO - Centre for Genomics and Oncological Research - Pfizer/University of Granada/Junta de Andalucía, PTS, Granada 18016, Spain
| | - Sonia Cabrera
- Otology & Neurotology Group CTS495, Department of Genomic Medicine, GENYO - Centre for Genomics and Oncological Research - Pfizer/University of Granada/Junta de Andalucía, PTS, Granada 18016, Spain
| | - Carmen Martín-Sierra
- Otology & Neurotology Group CTS495, Department of Genomic Medicine, GENYO - Centre for Genomics and Oncological Research - Pfizer/University of Granada/Junta de Andalucía, PTS, Granada 18016, Spain
| | - Steven D Price
- Department of Anatomy and Cell Biology, University of Illinois, Chicago, IL 60612, USA and
| | - Anna Lysakowski
- Department of Anatomy and Cell Biology, University of Illinois, Chicago, IL 60612, USA and
| | - José A Lopez-Escamez
- Otology & Neurotology Group CTS495, Department of Genomic Medicine, GENYO - Centre for Genomics and Oncological Research - Pfizer/University of Granada/Junta de Andalucía, PTS, Granada 18016, Spain, Department of Otolaryngology, Hospital de Poniente, El Ejido, Almería 04700, Spain
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A commentary on exome sequencing identifies a de novo mutation in HDAC8 associated with Cornelia de Lange syndrome. J Hum Genet 2014; 59:479. [PMID: 25102095 DOI: 10.1038/jhg.2014.68] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Renkema KY, Stokman MF, Giles RH, Knoers NVAM. Next-generation sequencing for research and diagnostics in kidney disease. Nat Rev Nephrol 2014; 10:433-44. [PMID: 24914583 DOI: 10.1038/nrneph.2014.95] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The advent of next-generation sequencing technologies has enabled genetic nephrology research to move beyond single gene analysis to the simultaneous investigation of hundreds of genes and entire pathways. These new sequencing approaches have been used to identify and characterize causal factors that underlie inherited heterogeneous kidney diseases such as nephronophthisis and congenital anomalies of the kidney and urinary tract. In this Review, we describe the development of next-generation sequencing in basic and clinical research and discuss the implementation of this novel technology in routine patient management. Widespread use of targeted and nontargeted approaches for gene identification in clinical practice will require consistent phenotyping, appropriate disease modelling and collaborative efforts to combine and integrate data analyses. Next-generation sequencing is an exceptionally promising technique that has the potential to improve the management of patients with inherited kidney diseases. However, identifying the molecular mechanisms that lead to renal developmental disorders and ciliopathies is difficult. A major challenge in the near future will be how best to integrate data obtained using next-generation sequencing with personalized medicine, including use of high-throughput disease modelling as a tool to support the clinical diagnosis of kidney diseases.
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Affiliation(s)
- Kirsten Y Renkema
- Department of Medical Genetics, University Medical Center Utrecht, KC04.048.02, PO Box 85090, Utrecht, 3508 AB, Netherlands
| | - Marijn F Stokman
- Department of Medical Genetics, University Medical Center Utrecht, KC04.048.02, PO Box 85090, Utrecht, 3508 AB, Netherlands
| | - Rachel H Giles
- Department of Nephrology and Hypertension, University Medical Center Utrecht, KC04.048.02, PO Box 85090, Utrecht, 3508 AB, Netherlands
| | - Nine V A M Knoers
- Department of Medical Genetics, University Medical Center Utrecht, KC04.048.02, PO Box 85090, Utrecht, 3508 AB, Netherlands
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