Molecular analysis of the APC gene in Sicilian patients with familial adenomatous polyposis (F.A.P.).

Familial adenomatous polyposis (FAP) is an autosomal dominant inherited syndrome, caused by germline mutations in the adenomatous polyposis coli (APC) suppressor gene. Patients with colorectal polyps are more likely to develop a malignant condition with poor prognosis. Typical FAP is characterized by hundreds to thousands of colorectal adenomatous polyps and by several extra-colonic manifestations; an attenuated form of polyposis (AFAP), presenting less than 100 adenomas and later onset, has been reported. In this study we have examined five Sicilian families affected by FAP syndrome, in order to provide predictive genetic testing for the affected families, as well as to contribute to mutation catalog enrichment. We have detected different APC mutations in these five pedigrees, confirming the remarkable heterogeneity of the mutational spectrum in FAP.