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Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Apr 26, 2023; 11(12): 2604-2620
Published online Apr 26, 2023. doi: 10.12998/wjcc.v11.i12.2604
Classification of osteogenesis imperfecta: Importance for prophylaxis and genetic counseling
Monica-Cristina Panzaru, Andreea Florea, Lavinia Caba, Eusebiu Vlad Gorduza
Monica-Cristina Panzaru, Lavinia Caba, Eusebiu Vlad Gorduza, Department of Medical Genetics, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, Iasi 700115, Romania
Andreea Florea, Department of Medical Genetics - Medical Genetics resident, “Grigore T. Popa” University of Medicine and Pharmacy, Iasi 700115, Romania
Author contributions: Panzaru MC, Caba L wrote the manuscript draft; Florea A performed the literature research; Panzaru MC and Gorduza EV wrote the review, and Gorduza EV supervised the manuscript.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Andreea Florea, MD, Doctor, Department of Medical Genetics - Medical Genetics resident, “Grigore T. Popa” University of Medicine and Pharmacy, 16 University Street, Iasi 700115, Romania. andreeaflorea97@gmail.com
Received: January 28, 2023
Peer-review started: January 28, 2023
First decision: March 10, 2023
Revised: March 18, 2023
Accepted: March 27, 2023
Article in press: March 27, 2023
Published online: April 26, 2023
Processing time: 87 Days and 11.3 Hours
Abstract

Osteogenesis imperfecta (OI) is a genetically heterogeneous monogenic disease characterized by decreased bone mass, bone fragility, and recurrent fractures. The phenotypic spectrum varies considerably ranging from prenatal fractures with lethal outcomes to mild forms with few fractures and normal stature. The basic mechanism is a collagen-related defect, not only in synthesis but also in folding, processing, bone mineralization, or osteoblast function. In recent years, great progress has been made in identifying new genes and molecular mechanisms underlying OI. In this context, the classification of OI has been revised several times and different types are used. The Sillence classification, based on clinical and radiological characteristics, is currently used as a grading of clinical severity. Based on the metabolic pathway, the functional classification allows identifying regulatory elements and targeting specific therapeutic approaches. Genetic classification has the advantage of identifying the inheritance pattern, an essential element for genetic counseling and prophylaxis. Although genotype-phenotype correlations may sometimes be challenging, genetic diagnosis allows a personalized management strategy, accurate family planning, and pregnancy management decisions including options for mode of delivery, or early antenatal OI treatment. Future research on molecular pathways and pathogenic variants involved could lead to the development of genotype-based therapeutic approaches. This narrative review summarizes our current understanding of genes, molecular mechanisms involved in OI, classifications, and their utility in prophylaxis.

Keywords: Osteogenesis imperfecta; Heterogeneity; Classification; Molecular mechanism; Genetic counseling; Prophylaxis

Core Tip: Osteogenesis imperfecta (OI) is a genetically heterogeneous systemic collagenous disorder with high phenotypic variability. Recent discoveries of new genes and molecular mechanisms underlying the disease have led to revisions of classical classification. Identifying the causative gene and molecular mechanisms allows a personalized management strategy, accurate family planning, and pregnancy management decisions including options for mode of delivery, or early antenatal OI treatment.