Behzad hatami, Ehsan Nazemalhosseini mojarad, Roya Kishani Farahani
Colorectal cancer (CRC) is a major cause for morbidity and mortality worldwide; it is the fourth most common cancer in men and the third most common cancer in women. CRC is divided into three categories: hereditary, nonhereditary and familial. Approximately 15% of CRC cases are considered as a hereditary form which most common contains: Familial adenomatous polyposis (FAP) and hereditary non polyposis colorectal cancer (HNPCC) and MYHAssociated polyposis (MAP). CRC develops through multiple pathways leading to different phenotypes.