MUTYH and polyposis: Besides these two major molecular types of CRC, two other well-defined alternative routes for CRC development have been described as follows: homozygous germline inactivation of the base excision repair gene mutY homologue (MUTYH) leading to a polyposis phenotype and the concomitant methylation of many gene loci resulting in the CpG island methylator phenotype (CIMP) [6].