BRCA1 and breast cancer: Considering the factors described above and the possible modifying effect conferred by polymorphisms, the objective of this study was to evaluate the frequency of the polymorphisms rs2981582, rs3803662, rs889312, rs3817198, and rs13281615 in women with breast cancer, with or without mutations in the BRCA1 and BRCA2 genes, and to correlate the frequency of the different polymorphisms with the family history of cancer in general and, more specifically with the history of breast and ovarian cancer and with the histopathological features of the tumors.