Mechanistically, the authors found that the receptor activator of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) ligand (RANKL), produced by monocytes, induced osteoclastogenesis (the process of formation and differentiation of osteoclasts from precursor cells, inducing bone remodeling) in RA. The gene discussed is TNFSF11; the disease is rheumatoid arthritis.