Auto-Abs against IL-17A, IL-17F, and/or IL-22 are detected in >90% of patients with APS-1, in whom CMC is a hallmark of the disease (Kisand et al., 2021; Philippot et al., 2021; Puel and Casanova, 2021; Wolff et al., 2013). The gene discussed is IL17F; the disease is autoimmune polyendocrine syndrome type 1.