The discovery of the RANK-RANKL pathway has led to the development of denosumab, a fully human antibody that binds to and inhibits RANKL, thus preventing bone resorption, which has been shown to reduce the risk of vertebral, nonvertebral, and hip fractures in postmenopausal women with osteoporosis [37]. The gene discussed is TNFSF11; the disease is osteoporosis.