MSH6 is a gene commonly associated with Hereditary Non-Polyposis Colorectal Cancer (HNPCC). HNPCC is an autosomal, dominantly inherited disease associated with marked increase in cancer susceptibility. It is characterized by a familial predisposition to early onset Colorectal Carcinoma and extra-colonic cancers of the gastrointestinal, urological and female reproductive tracts. HNPCC is reported to be the most common form of inherited Colorectal Cancer in the western world. MSH6 is a mismatch repair gene which is deficient in a high proportion of patients with microsatellite instability (MSI-H).