The studies successfully demonstrated that hMSH2- Asp/Asp (OR 9.16; 95% CI 5.57–15.07, p < .0001), XPD-Gln/Gln (OR 3.72; 95% CI 2.44–5.68, p < .0001) and RAD51-T/T genotypes (OR 1.90; 95% CI 1.21–2.97, p = 0.007) were strongly associated with an increased risk of breast cancer. This evidence concerns the gene MSH2 and breast cancer.