HMGB1, TLR4, IL‐23, and IL‐17A serum concentrations in psoriasis patients were significantly elevated compared with those in healthy controls (t = 7.716, 2.433, 4.443, and 10.339, respectively, all p < .05 or .01, Table 2, Figure 1A–D). This evidence concerns the gene IL17A and psoriasis.