Subgroup analysis by ancestry categories revealed a significant association between PPARG rs1801282 polymorphisms and T2DM in the European populations under allelic (OR: 0.82, 95% CI: 0.73–0.91), homozygous (OR: 0.74, 95% CI: 0.59–0.92), heterozygous (OR: 0.88, 95% CI: 0.79–0.98), additive (OR: 0.76, 95% CI: 0.58–0.98), dominant (OR: 0.86, 95% CI: 0.77–0.96), recessive (OR: 0.75, 95% CI: 0.61–0.93), and co-dominant (OR: 0.88, 95% CI: 0.82–0.95) genetic models (Table 3). The gene discussed is PPARG; the disease is type 2 diabetes mellitus.