Three SNPs in the McKusick-Kaufman syndrome (MKKS) gene were significantly related to metabolic syndrome by case-control association study; rs1545 (odds ratio (OR) adjusted for age and gender, 1.45; 95% confidence interval (CI), 1.21-1.74; P=0.000043 (additive model)); rs1547 (OR, 1.45; 95% CI, 1.21-1.74; P=0.000041); and rs2294901 (OR, 1.46; 95% CI, 1.22-1.75; P=0.000033).