The overall analysis showed a significant association between the ACE I/D polymorphism and the risk of diabetic nephropathy for all genetic models (ID versus II: OR = 1.12, 95% CI 1.02–1.24; DD versus II: OR = 1.27, 95% CI 1.13–1.44; allele contrast: OR = 1.15, 95% CI 1.08–1.23; dominant model: OR = 1.18, 95% CI 1.07–1.31; and recessive model: OR = 1.18, 95% CI 1.08–1.30, resp). This evidence concerns the gene ACE and diabetic kidney disease.