Mutations analysis of BRCA1 gene in patients with breast cancer in South Khorasan province, East Iran

Background: Breast cancer (BC) is well-known as the most common malignancy and the first leading cause of cancer-related death among women worldwide. Evidence suggests that familial history and age are important risk factors for the development of this disease in Iran. Mutations in BRCA1 and BRCA2 genes are the cause of 5 to 10% of hereditary BC. Recent studies demonstrated that mutations in BRCA1 were observed in high-risk women with family histories of BC. However, to date, the mutations have not been elucidated in BC patients from east of Iran. The purpose of this study was to analyze BRCA1 mutations in BC patient from South Khorasan Province. Methods: In the present study, 88 BC patients (11 positive family history) were screened for mutations in BRCA1. The analysis of BRCA1 was carried out by SSCP (single-strand conformation polymorphism) for shorter exons and direct sequencing in the case of longer ones. Results: Twenty-eight of the patients (31.8%) had a synonymous mutation (c.4308T>C) in exon 13. A missense mutation (c. 4837A>G) was presented in exon 16 with a frequency of 56.8 %. In exon 11 three missense mutations were observed, and the frequency rate for c.3113A>G was 32.5%, for c.3119G>A was 5%, and the highest frequency belonged to c.3548A>G with 72.4% in familial BC and 45.4% in the non-familial group. Conclusion: In our study, five mutations were found, but none of the founder mutations were identified in this population. Two missense mutations in exon 16 (56.8%) and in exon 11 (65%) had the highest frequency in South Khorasan Province.