Background: A PlA1/A2 polymorphism of glycoprotein IIIa is known to be involved in the pathogenesis of arterial thrombosis, myocardial infarction, stroke and type 2 diabetes, but there is no evidence of association with diabetic retinopathy. The aim of this study was to examine the role of the PlA1/A2 polymorphism of the glycoprotein IIIa gene in the development of diabetic retinopathy in Caucasians with type 2 diabetes.
Design: Cross-sectional case–control study.
Participants: Totally 222 patients with diabetic retinopathy and 120 diabetic subjects without clinical signs of diabetic retinopathy from the Eye Clinic, University Medical Centre Ljubljana were enrolled in the study.
Methods: Fundus examination and blood biochemical analysis were performed. The polymerase chain reaction and restriction fragment length polymorphism were used.
Main Outcome Measures: The total cholesterol, triglyceride, high-density lipoprotein levels, fasting blood glucose and HbA1c were measured, and the genotypes of the PlA1/A2 polymorphism were determined.
Results: Patients with diabetic retinopathy had earlier onset, longer duration of type 2 diabetes and a higher incidence of insulin therapy compared to the diabetic patients without diabetic retinopathy. A significantly lower frequency of the A2A2 genotype of glycoprotein IIIa was found in diabetic patients with retinopathy compared to those without retinopathy (odds ratio = 0.49, 95% confidence interval = 0.28–0.89; P = 0.018).
Conclusions: The A2A2 genotype of the glycoprotein IIIa polymorphism was associated with lower risk for diabetic retinopathy in Caucasians with type 2 diabetes. Further studies are needed to elucidate its protective role in the development of diabetic retinopathy in Caucasians.