Frame-shift mutations in BRCA1 and BRCA2 genes in Turkish families with breast and/or ovarian cancer

Abstract

It is well established that mutations in BRCA1 and BRCA2 genes significantly increase the risk of breast and/or ovarian cancer. Notably frame-shift mutations of BRCA1 and BRCA2 genes were linked to high risk. To date, all of studies in our country investigated a total of 415 Turkish high-risk families for germline BRCA1 and BRCA2 mutations using a variety of screening techniques. The authors found that the rate of germline mutations in both genes among high-risk Turkish families was approximately 10 percent, which is consistent with our finding. About eighty percent of the total mutation rate contain frame-shift mutations. These frame-shift mutations were analyzed 29 different types. They were detected 15 in BRCA1 and 14 in BRCA2. Sixteen of these mutations were novel in Turkish families. In analyzing Turkish high-risk families, no founder mutations in BRCA1/BRCA2 genes were detected. One exception is the 5382insC BRCA1 gene mutation. The data from all Turkish patients with breast and/or ovarian cancer indicate that only the 5382insC mutation occurs at a low rate ( 6/415-about 1.45%) in Turkish patients. Yet, none of the other frame-shift mutations was incorporated into the Turkish population. Our findings suggest that there are no predominant frame-shift mutations in BRCA1/BRCA2 gene in Turkish high risk families. Our contribution broadens the BRCA1/BRCA2 world mutational spectra.