TNF‐α, which is produced by many types of cells including monocytes and macrophages, has been proved to involve in bone resorption, particularly in inflammatory bone diseases such as rheumatoid arthritis127 and aseptic periprosthetic osteolysis.128 TNF‐α have been speculated to act directly by enhancing proliferation and activity of cells in the osteoclast lineage, or indirectly by affecting the production of osteoclast differentiation factors via osteoblast/stromal cells such as RANKL and its soluble decoy receptor, osteoprotegerin (OPG).111, 129. The gene discussed is TNF; the disease is bone inflammation disease.