ESR1 and breast cancer: With respect to ERCC2 gene, the haplotype composed of the 2 minor alleles (rs1799793/A - rs13181/C) was significantly associated with positive ER and PR expressions in BC tumors (ER: OR: 0.28, 95% CI: 0.09–0.88, p = 0.03; PR: OR: 0.33, 95% CI: 0.12–0.92, p = 0.017).