MRC1 and Lynch syndrome: Individuals with hereditary predisposition to Lynch syndrome (hereditary nonpolyposis colorectal cancer) harbor germline mutations in one of the following DNA MMR genes: MLH1, MSH2, MSH6, PMS2, or EPCAM. EC is one of the most frequently occurring extracolonic malignancies in patients with Lynch syndrome, and about up to 5% of ECs are caused by hereditary genetic aberrations [44, 45].