Colorectal Cancer
Copyright ©2005 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 14, 2005; 11(42): 6620-6623
Published online Nov 14, 2005. doi: 10.3748/wjg.v11.i42.6620
Detection of germline mutations of hMLH1 and hMSH2 based on cDNA sequencing in China
Chao-Fu Wang, Xiao-Yan Zhou, Tai-Ming Zhang, Meng-Hong Sun, Da-Ren Shi
Chao-Fu Wang, Xiao-Yan Zhou, Tai-Ming Zhang, Meng-Hong Sun, Da-Ren Shi, Laboratory of Molecular Pathology, Cancer Hospital of Fudan University; Department of Oncology, Shanghai Medical College of Fudan University, Shanghai 200032, China
Author contributions: All authors contributed equally to the work.
Supported by the Key Programs of Shanghai Medical Subjects, No. 05 Ш 004
Correspondence to: Dr. Xiao-Yan Zhou, Laboratory of Molecular Pathology, Cancer Hospital of Fudan University, 270 Dongan Road, Shanghai 20032, China. xyzhou100@yahoo.com
Telephone: +86-21-64175590-3646
Received: March 18, 2005
Revised: April 15, 2005
Accepted: April 18, 2005
Published online: November 14, 2005
Abstract

AIM: To detect the germline mutations of hMLH1 and hMSH2 based on mRNA sequencing to identify hereditary non-polyposis colorectal cancer (HNPCC) families.

METHODS: Total RNA was extracted from peripheral blood of 14 members from 12 different families fulfilling Amsterdam criteria II. mRNA of hMLH1 and hMSH2 was reversed with special primers and heat-resistant reverse transcriptase. cDNA was amplified with expand long template PCR and cDNA sequencing analysis was followed.

RESULT: Seven germline mutations were found in 6 families (6/12, 50%), in 4 hMLH1 and 3 hMSH2 mutations (4/12, 33.3%); (3/12, 25%). The mutation types involved 4 missense, 1 silent and 1 frame shift mutations as well as 1 mutation in the non-coding area. Four out of the seven mutations have not been reported previously. The 4 hMLH1 mutations were distributed in exons 8, 12, 16, and 19. The 3 hMSH2 mutations were distributed in exons 1 and 2. Six out of the 7 mutations were pathological, which were distributed in 5 HNPCC families.

CONCLUSION: Germline mutations of hMLH1 and hMSH2 can be found based on cDNA sequencing so as to identify HNPCC family, which is highly sensitive and has the advantages of cost and time saving.

Keywords: hMLH1; hMSH2; Colorectal cancer; Hereditary non-polyposis; Reverse transcription; Germline mutation