Abstract: Oxidative stress plays an important role in the pathogenesis of cardiovascular alterations observed in diabetic patients and that hyperglycemia is the causal link between diabetes and increased oxidative stress. Evidence suggests that Ser326Cys, a genetic polymorphism of (8-OxoGuanine Glycosylase 1 OGG1) is associated with coronary artery lesions in patients with diabetes mellitus type 1 however, the underlying mechanism is unclear.