Specifically the overwhelming majority of hereditary nonpolyposis colorectal cancers (HNPCC) are attributed to mutations in the genes encoding the MutS and MutL homologues MSH2 and MLH1 respectively, which allows them to be classified as tumour suppressor genes.
Hereditary nonpolyposis colorectal cancer (HNPCC) is very often caused by a defective MSH2 gene leading to defective mismatch repair, but displays no symptoms of "accelerated aging".
Deletion of a portion of the 3’ end of the EpCAM gene causes epigenetic inactivation of the MSH2 gene by hypermethylating the promoter region of the MSH2 gene.
Under the name constitutional mismatch repair-deficiency, (CMMR-D), it has been mapped to MLH1, MSH2, MSH6 or PMS2.
The most frequent mutations in HNPCC are mutations in the MSH2 and MLH1 genes.
MSH2 |