BRCA1 and breast carcinoma: The pooled prevalence of BRCA1 mutation among Breast Cancer Patients was 11% (95% CI: 4–21%) [4, 5, 7, 17, 19–25], and there was a substantial heterogeneity across the studies (Chi-square = 79.3, P value < 0.001, I-square = 87.38%).