Specific immunomodulatory therapies by antibodies in humans to neutralize the IL-17A activating cytokine IL-23 or the effector cytokine IL-17A itself have been successful in the treatment of psoriasis, psoriatic arthritis, rheumatoid arthritis and ankylosing spondylitis [8, 10–15]. The gene discussed is IL17A; the disease is rheumatoid arthritis.