Importantly, the bone resorption is stimulated by the receptor activator of nuclear factor-κB ligand (RANKL), but negatively regulated by its decoy receptor, osteoprotegerin (OPG) [11], suggesting that attenuation of RANKL/OPG ratio may prevent osteoclastogenesis and bone resorption in periodontitis. The gene discussed is TNFSF11; the disease is periodontitis.