Interleukin-33 (IL-33), a novel member of the IL-1 family, has recently been implicated in several inflammatory and autoimmune diseases, including atherosclerosis, sepsis, asthma, allergy, Crohn's disease, ankylosing spondylitis, arthritis, and systemic lupus erythematosus [5, 6]. This evidence concerns the gene IL33 and ankylosing spondylitis.