The first attempts to target TNFα were made decades ago, with the understanding that this cytokine was the major mediator of inflammation and its deregulation was implicated in a variety of autoimmune diseases, such as rheumatoid arthritis (RA), multiple sclerosis, psoriasis, Crohn’s disease, scleroderma, systemic lupus erythematosus, ankylosing spondylitis, and diabetes. The gene discussed is TNF; the disease is Crohn disease.