For TNF-α 238 G/A polymorphism, TNF-α 238 G/A polymorphism was associated with increased risk of psoriasis under three genetic models (For A versus G: fixed-effects OR 2.46, 95%CI 2.04-2.96, P < 0.001; for AG versus GG: fixed-effects OR 2.69, 95%CI 2.20-3.28, P < 0.001; for AA/AG versus GG: fixed-effects OR 2.68, 95%CI 2.20-3.26, P < 0.001) when all 14 studies were pooled into the meta-analysis (Figure 4, Figure 5, and Figure 6, Table 2). The gene discussed is TNF; the disease is psoriasis.