A study involving 33 patients with autoimmune polyendocrine syndrome type 1 (APS-1, also known as APECED) presenting with CMC detected high titers of ACAAs against IL-17A, IL-17F, and/or IL-22, and no such autoantibodies were observed in 37 healthy controls or the 103 patients with other autoimmune disorders (20). This evidence concerns the gene IL17F and autoimmune disease.