Biallelic inactivating germline mutations in the MUTYH gene predispose to MUTYH-associated polyposis (MAP; MIM# 608456), an autosomal recessive disorder characterized by multiple colorectal adenomas and carcinomas (Al-Tassan et al., 2002; Jones et al., 2002; Sampson et al., 2003; Sieber et al., 2003). This evidence concerns the gene MUTYH and mutyh-associated polyposis.