We also grouped the women into RANKL/OPG tertiles across all controls (not only within a given progesterone tertile) and again women within the high progesterone/high RANKL/OPG group had a 4.2 (95% CI 1.3 - 16.0, p = 0.02) fold risk for developing breast cancer. This evidence concerns the gene TNFRSF11B and breast cancer.