APC and attenuated familial adenomatous polyposis: A milder form of FAP, termed attenuated FAP (AFAP), is characterized by the development of less than 100 colorectal adenomas, a more limited expression of extracolonic features, and a delay in onset of CRC; germline mutations associated with AFAP have mainly been detected in the 5′ and 3′ end of APC, and in the alternatively spliced exon 9 of the gene (reviewed by Jasperson et al., 2010).