In the meta-analysis performed by Drummond et al., they showed a dose-dependent association of high levels of SHBG with a low risk of developing BC in postmenopausal women (OR = 0.54) and the absence of significant relationships in premenopausal women (OR = 0.96; p > 0.05) and in groups of patients with different ER status (positive/negative) [45]. This evidence concerns the gene ESR1 and breast cancer.