This study was inspired by the high rate (30–40%) of non-responsiveness to therapeutic anti-TNFA antibodies, which are used to treat multiple debilitating autoimmune diseases like rheumatoid arthritis, Crohn’s disease, ulcerative colitis, psoriasis, psoriatic arthritis, and ankylosing spondylitis. The gene discussed is TNF; the disease is ankylosing spondylitis.