Inhibition of BTK-dependent processes such as B cell receptor-mediated B cell functions, IgG-containing immune complex signaling through Fcγ receptors in monocytic cells, and RANK-dependent osteoclastogenesis is expected to provide benefit in the treatment of autoimmune disorders such as RA, where these pathways are involved in disease pathogenesis [9, 10]. The gene discussed is BTK; the disease is autoimmune disease.