Consistent with the previous finding that mutations in the 5' and 3' ends and in exon 9 of the APC gene are associated with having the attenuated type of FAP [6-10], the mutations in exon 4 were found in the 3 AFAP patients in this study, and the mutations in exons 14, and 15 were found in the 5 classical FAP patients in this study. Here, APC is linked to attenuated familial adenomatous polyposis.