Single nucleotide polymorphisms (SNPs) may modify the risk of cancer. They may be then regarded as potential markers of carcinogenesis. The aim of this study was to analyze the frequency of genotypes and alleles of SNPs in DNA repair genes and to investigate the influence this genetic variation exerts on breast cancer in Polish females. The test group comprised 600 females with breast cancer and 600 healthy controls. Genomic DNA was isolated and the SNPs in DNA repair genes were determined by High-Resolution Melter (HRM) technique. Following polymorphisms were analysed: Arg399Gln (rs25487) of the XRCC1, Gly322Asp (rs4987188) of the hMSH2, Lys751Gln (rs13181) of the XPD, Arg188His (rs3218536) of the XRCC2, P871L (rs799917) of the BRCA1 and N372H (rs144848) of the BRCA2 gene. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each genotype and allele. Statistically significant correlations were identified between 4 single nucleotide polymorphisms and the breast cancer risk: rs25487 rs4987188 rs13181 and rs799917. The alleles XRCC1-Gln (OR 5.11; 95% CI 5.68-11.64, p < .0001), hMSH2-Asp (OR 4.66; 95% CI 3.90-5.56, p < .0001), XPD-Gln (OR 2.65; 95% CI 2.24-3.14, p < .0001) and BRCA1-L (OR 1.45; 95% CI 1.24-1.71, p < .0001) genes were strongly correlated with this malignancy. No correlation was found between the studied SNPs and tumor grading nor the lymph node status. Further research on larger groups is warranted to determine the influence of above-mentioned genetic variants on breast cancer risk.
Keywords: Breast cancer; DNA repair; Single nucleotide polymorphism.