The investigation of the downstream signaling pathways associated with the RANKL-RANK axis in osteoclastogenesis has uncovered numerous shared molecules and signaling mechanisms that link bone and immune cells.255 Mice deficient in immunoreceptor tyrosine-based activation motif (ITAM)-containing adapters, specifically the Fc receptor common gamma subunit (FcRγ) and DNAX-activating protein (DAP)12, display pronounced osteopetrosis due to compromised osteoclast differentiation. Here, TNFRSF11A is linked to osteopetrosis.