MUTYH and colorectal carcinoma: Furthermore, several studies have found that none of the patients, who had biallelic germline MUTYH mutations (N=63), presented with a phenotype consistent with severe classical FAP, the criteria being: more than 1000 polyps or early-onset CRC (before the age of 50 years), and the development of more than 100 polyps before the age of 35 years, respectively [40, 85, 86].