The germline mutations of breast cancer susceptibility genes 1 (BRCA1) and 2 (BRCA2) are the two most frequently mutated genes in inherited breast and ovarian cancer. Among the most known mutations in these tumor suppressor genes are 5382insC and 185delAG in BRCA1 and 6174delT in BRCA2. The aim of the current study was to investigate the frequency of these BRCA1 and BRCA2 mutations in Western Turkish population. Twenty-five women with a history of self breast cancer and family history, 25 women with a familial history of breast cancer in their first degree-relatives and five healthy women formed the studied groups. DNA from peripheral blood was extracted and analyzed by high-resolution melting (HAM) analysis. None of the 50 patients and five healthy individuals was found to carry 185delAG mutation in BRCA1 and the 6174delT mutation in BRCA2. But, we found the 5382insC mutation in exon 20 of BRCA1 in five patients, having a strong family history. Four of these five patients were from the same family. Our preliminary results indicate that penetrance of 5382insC mutation in BRCA1 mutations is dominant in Turkish population; however, it seems there might be some other genes that contribute more significantly to familial breast carcinoma in Turkish population in BRCA.