Heteroduplex Analysis of Causative APC Mutations in FAP Patients Referred for Genetic Counseling in Mashhad Ghaem Hospital, Iran

Since the isolation and characterization of the adenomatous polyposis coli (APC) gene in 1991, none of the currently available techniques were able to detect 100% of the germline mutations. In the present study we have used Heteroduplex Analysis (HA) and followed by DNA sequencing to test in an exhaustive analysis of entire APC coding region in a group of 26 unrelated Khorasanies patients with familial adenomatous polyposis (FAP). Sixtheen causative mutations (61.5%) were detected. This study shows that HA is less sensitive for single base pair substitutions, whereas mutations related to insertions or deletions are easier to detect by the HA method. Since more than 70% of APC mutations are small deletion (66%) or small insertions (6%), therefore HA is particularly suitable for the APC mutation detection.