Association of common BRCA1 variants with predisposition to breast tumors in Pakistan

Abstract

BRCA1 variants are extensively associated with increased risk of breast cancer. Early detection and screening of variants is still rare in developing countries. Here, we investigated six BRCA1 variants in 300 subjects from Pakistani population using tetra amplification-refractory mutation system (T-ARMS) PCR. Our results indicate significant association of BRCA1 variants rs8176237 (AA; OR 8.2, 95% CI 3.02–22.64, p < 0.0001), rs1060915 (CC; OR 4.29, 95% CI 1.94–9.48, p = 0.0003), and rs799912 (TT; OR 3.16, 95% CI 1.44–6.94, p = 0.004) with up to 8-fold increased odds of breast cancer under recessive model. Furthermore, BRCA1 haplotypes AGCACG and AGCCCT were associated with up to 18% breast cancer cases (p < 0.05). Additionally, we found association of these variants with up to 11-fold increased odds of benign breast tumors. Linkage disequilibrium (LD) block-wise analysis revealed haplotypes GCAC and ATAC were associated with significantly increased risk. To our knowledge, this is the first study that identifies the association of these BRCA1 variants with breast tumors in Pakistani population. In conclusion, BRCA1 variants investigated in the present study are associated with high odds of benign- and malignant breast tumors. Studies with bigger sample size may help early detection and screening to reduce the odds of breast cancer.