Mutations of Chromosome 5q21 Genes in FAP and Colorectal Cancer Patients

TLDR

Genes on chromosome 5q21 are implicated in inherited FAP and GS and in sporadic colorectal cancer development. The study aims to identify these genes to enhance understanding, diagnosis, and counseling for inherited colorectal cancer. Somatic alterations of MCC and APC were detected in tumors from sporadic colorectal cancer patients. Germ‑line APC mutations were found in FAP and GS patients, indicating that multiple 5q21 genes contribute to colorectal neoplasia.

Abstract

Previous studies suggested that one or more genes on chromosome 5q21 are responsible for the inheritance of familial adenomatous polyposis (FAP) and Gardner's syndrome (GS), and contribute to tumor development in patients with noninherited forms of colorectal cancer. Two genes on 5q21 that are tightly linked to FAP (MCC and APC) were found to be somatically altered in tumors from sporadic colorectal cancer patients. One of the genes (APC) was also found to be altered by point mutation in the germ line of FAP and GS patients. These data suggest that more than one gene on chromosome 5q21 may contribute to colorectal neoplasia, and that mutations of the APC gene can cause both FAP and GS. The identification of these genes should aid in understanding the pathogenesis of colorectal neoplasia and in the diagnosis and counseling of patients with inherited predispositions to colorectal cancer.