BRCA1 and breast carcinoma: However, there might be variation in BRCA1/2 mutation prevalence across race and ethnicity for breast cancer patients with high-risk factors, although the prevalence of BRCA1/2 mutations is comparable among sporadic breast cancer patients of African, Asian, White, and Hispanic descent: approximately 1–4% per gene, with the exception of Ashkenazi Jewish and Icelandic patients [33, 34].