MLH1 and colorectal cancer: For instance, in families with a history of hereditary nonpolyposis colorectal cancer, there is evidence of heritable germline inheritance of hypermethylated promoter region in DNA mismatch repair genes including mutL homolog 1 (MLH1) and mutL homolog 2 (MLH2) alleles that suggests individuals who inherited these epimutations have a predisposition to this particular type of cancer [22], [23], [37].