In a new study, A Disintegrin and Metalloprotease Domain containing Thrombospondin Type 1 Motif-like 5 (ADAMTSL5), a protein important for microfibril function, was found to be produced by melanocytes and when presented by HLA-C*06:02 can be an activating antigen for IL-17-producing CD8+ T cells in psoriasis [7]. The gene discussed is IL17A; the disease is psoriasis.