Meta-analysis of the IL-4 -1099T/G showed no association between the polymorphism and periodontitis susceptibility (G versus T: OR = 1.2, 95% CI = 0.53–2.71; GG versus TT OR = 6.58, 95% CI = 0.03–11.46; TG versus TT: OR = 0.57, 95% CI = 0.32–1.04; GG + TG versus TT: OR = 0.73, 95% CI = 0.23–2.34; GG versus TT + TG: OR = 0.63, 95% CI = 0.03–11.35) (Table 4). The gene discussed is IL4; the disease is periodontitis.