nominally significantP = 0.017
Three intronic variants of XDH gene were nominally significant, including rs513311 (intron 3) (OR = 2.10, 95% CI = 1.14–3.85, P = 0.017; rs561525 (intron 9) (OR = 2.18, 95% CI = 1.04–4.59, P = 0.040), and rs2163059 (intron 12) (OR = 0.75, 95% CI 0.58–0.96, P = 0.026).