MUTYH and familial adenomatous polyposis 2: MUTYH-associated polyposis (MAP) is an autosomal recessive disorder, which may be responsible for approximately 0.5–1% of colorectal carcinomas (CRCs).[1,2] Most biallelic MUTYH mutation carriers are reported to develop multiple polyps (typically between 10–500).[3,4] However, in seven population based CRC studies, 15 out of 39 (38%) proven biallelic MUTYH mutation carriers had no polyps besides their CRC while seven (18%) had a limited number of adenomas (i.e. <10).