Currently, the pathogenesis of psoriasis is focused on the IL‐23‐Th17 axis, and the related cytokines IL‐23, IL‐17A, and IL‐22 play a key role in the pathogenesis of psoriasis, and secukinumab, which antagonizes IL‐17A, has shown very good efficacy in the clinical treatment of psoriasis. The gene discussed is IL17A; the disease is psoriasis.