BRCA1 and BRCA2 mutations in the ovarian cancer population across race and ethnicity: Special reference to Asia

Objective: To evaluate the prevalence and spectrum of BRCA mutations among ovarian carcinoma patients of different races and ethnicity with special reference to Asia. Methods: A systematic review of the literature was undertaken to evaluate the prevalence of BRCA mutations among people belonging to different races. The electronic search strategy was developed specifically for the different databases concerned and via cross-referencing. Results: The frequency of BRCA1 and BRCA2 mutations ranged from 1.1 to 39.7 and from 0 to 13.9, respectively. BRCA1 mutations are more common among ovarian cancer cases than BRCA2 mutations, although the ratio of BRCA1 to BRCA2 varies between populations. The Swedish and Indian populations showed 12 and 7 times as many BRCA1 as BRCA2 mutations, respectively, whilst in a study from Iceland the ratio was 0.5:1. These wide-ranging estimates of the mutation prevalence suggest genetic heterogeneity between different populations. Conclusion: The ability to identify BRCA1/2 mutations was found to be successful in the clinical management of ovarian cancer. Given the implications for clinical care and for advances in cancer prevention, identifying racial difference in genetic or lifestyle factors, which may modify the cancer risk due to BRCA1/2 mutations, is a high priority for future research.