APC and Familial adenomatous polyposis: Syndromes that place patients at high risk for CRC include familial adenomatous polyposis (FAP), the result of an autosomal dominant (AD) germline mutation of the APC (adenomatous polyposis coli) gene on chromosome 5q, and hereditary nonpolyposis colon cancer (HPNCC) that is a result of mutated mismatch repair genes; see reviews [12, 13].