Thus, reliable genetic tests are already available to detect phenotypically well-characterized familial forms of CRC associated with high-penetrance alleles of genes, including APC in familial adenomatous polyposis (FAP), DNA mismatch repair genes in Lynch syndrome or hereditary non-polyposis colorectal cancer (HNPCC), and MUTYH in MUTYH-associated polyposis (MAP) [3]. The gene discussed is APC; the disease is hereditary nonpolyposis colon cancer.