Large genomic aberrations in MSH2 and MLH1 genes are frequent in Chinese colorectal cancer.

نویسندگان

  • Ming Zhu
  • Jintian Li
  • Xiaomei Zhang
  • Xiaorong Liu
  • Waltraut Friedl
  • Yuanying Zhang
  • Xiaoliu Wu
  • Peter Propping
  • Yaping Wang
چکیده

Hereditary nonpolyposis colorectal cancer is caused by inactivating mutations in the genes of the DNA mismatch repair (MMR) system. Studies have shown that large-fragment aberrations in MMR genes are responsible for a considerable proportion of hereditary colorectal cancer (CRC), but it has been rarely reported in Chinese patients. Here we used multiplex ligation-dependent probe amplification to analyze the genomic rearrangements of 45 Chinese hereditary CRC families, 20 young-age CRC patients (onset of CRC at younger than 50 years and no family history), and 13 patients with sporadic CRC diagnosed at age 50 years or older. Overall, we found 9 (13.8%) large genomic deletions or duplications: 7 out of 45 CRC patients with family history and 2 out of 20 young CRC patients. In all alterations, five genomic deletions were uncovered in the MSH2 gene, as well as one deletion and three duplications in the MLH1 gene. Furthermore, two of the duplications unveiled in this study may have more than a four-copy increase of the exon showing duplication in MLH1. The results indicate that genomic aberrations, large-fragment deletions and duplications, in both MSH2 and MLH1 genes play a role in the pathogenesis of Chinese CRC patients with a family history, as reported in western populations. Moreover, the genomic aberrations in these genes might also be a frequent cause of CRC at a young age in China.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

سه موتاسیون ژرم لاین جدید در ژن MLH1 در بیماران مبتلا به سرطان کولورکتال ارثی

Abstract Background: Hereditary non-polyposis colorectal cancer is the most common cause of early onset of hereditary colorectal cancer. In the majority of Hereditary non-polyposis colorectal cancer families, microsatellite instability and germline mutation in one of the DNA mismatch repair genes in clouding MSH2, MLH1, MSH6 and PMS2 are found. The Objective of this study was to determine th...

متن کامل

Gene conversion is a frequent mechanism of inactivation of the wild-type allele in cancers from MLH1/MSH2 deletion carriers.

Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominantly inherited cancer predisposition syndrome caused by germ line mutations in DNA mismatch repair genes, predominantly MLH1 and MSH2, with large genomic rearrangements accounting for 5% to 20% of all mutations. Although crucial to the understanding of cancer initiation, little is known about the second, somatic hit in HNPC...

متن کامل

Genomic rearrangements in MSH2, MLH1 or MSH6 are rare in HNPCC patients carrying point mutations.

Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant disease with high penetrance, caused by germline mutations in the mismatch repair (MMR) genes MLH1, MSH2, MSH6, PMS2 and MLH3. Most reported pathogenic mutations are point mutations, comprising single base substitutions, small insertions and deletions. In addition, genomic rearrangements, such as large deletions and dupl...

متن کامل

MSH2 in contrast to MLH1 and MSH6 is frequently inactivated by exonic and promoter rearrangements in hereditary nonpolyposis colorectal cancer.

To estimate the relative frequency of mismatch repair genes, rearrangements in hereditary nonpolyposis colorectal cancer (HNPCC) families without detectable mutations in MSH2 or MLH1, we have analyzed by multiplex PCR of short fluorescent fragments MSH2, MLH1, and MSH6 in 61 families, either fulfilling Amsterdam criteria or including cases of multiple primary cancers belonging to the HNPCC spec...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Cancer genetics and cytogenetics

دوره 160 1  شماره 

صفحات  -

تاریخ انتشار 2005