In premenopausal females there is a balance however, in postmenopausal females decrease in estrogen leads to increase expression of RANKL which then by passes OPG and leads to increase binding with RANK causing increase in osteoclast function and ultimately increase in bone resorption with eventual osteoporosis.39 The role of OPG as a biomarker in patients with osteoporosis is under consideration. The gene discussed is TNFSF11; the disease is osteoporosis.