Phenotypic Expression of Disease in Families That Have Mutations in the 5′ Region of the Adenomatous Polyposis Coli Gene

Abstract

Families with adenomatous polyposis that have proximal 5' mutations of the adenomatous polyposis coli gene are more likely to have a heterogeneous phenotype with delayed development of colonic polyposis and colorectal cancer than are families with distal 5' mutations of the gene. Management should include genotyping of patients who are at risk, colonoscopic surveillance of genotypically positive persons, and prophylactic colectomy if several adenomas are found.