Association of the nitric oxide synthase gene polymorphism with an increased risk for progression to diabetic nephropathy in type 2 diabetes.

370 Japanese individuals, including 215 type 2 diabetic patients (82 without nephropathy, 94 with microalbuminuria, 39 with nephropathy) and 155 healthy control subjects.

Presence of the endothelial nitric oxide synthase (ecNOS) tandem repeat polymorphism (ecNOS4a allele).

Absence of the ecNOS4a allele (noncarriers).

Progression to diabetic nephropathy.