Immune-related cells including dendritic cells (DCs) and T helper (Th) 17 cells, along with Toll-like receptors(TLRs) and cytokines such as interferon (IFN)-α, tumor necrosis factor (TNF)-α, IFN-γ, Interleukin(IL)-12, IL-22, IL-23, and IL-17, are responsible for the pathogenesis of psoriasis [2]. The gene discussed is IL17A; the disease is psoriasis.