Denosumab is a human monoclonal IgG2 antibody against RANKL and has been approved for the treatment of osteoporosis in postmenopausal women, women with breast cancer taking aromatase inhibitors, and men at high risk of fracture, such as prostate cancer patients undergoing androgen deprivation therapy.420–422 In addition, denosumab has been approved for treating GC-induced osteoporosis in both women and men at high risk of fracture. The gene discussed is CYP19A1; the disease is breast cancer.