Lynch syndrome, or hereditary nonpolyposis CRC, is caused by an inherited alteration in one of the MMR genes (MLH1 (OMIM,120436), MSH2 (OMIM, 609309), MSH6 (OMIM, 600678), PMS2 (OMIM, 600259) and EPCAM (OMIM, 185535)). This evidence concerns the gene MSH2 and Lynch syndrome.