Background: Polymorphisms of the receptor for advanced glycation end products (RAGE) gene have been associated with diabetes, coronary artery disease (CAD) and inflammatory processes. The -374T >A RAGE gene promoter polymorphism was shown to affect gene transcription. The aim of this study was to evaluate the association of the -374T >A polymorphism with the severity of CAD in patients with or without type 2 diabetes mellitus.
Methods: We studied 246 Euro-Brazilians with angiographically defined CAD (stenosis >50%), comprising type 2 diabetic (n=98) and non-diabetic subjects (n=148). Genotyping was performed by PCR-restriction fragment length polymorphism using Tsp509I restriction enzyme.
Results: The AA genotype was associated with a significant decrease in CAD severity estimated by the number of diseased vessels (1.43+/-0.5 vs. 2.49+/-1.1; p=0.002) and the Duke score (27.3+/-10.8 vs. 49.3+/-20.1; p=0.001) only in the group of CAD subjects with type 2 diabetes mellitus. The protective effect of the AA genotype against severity of CAD was not observed in the non-diabetic group.
Conclusion: This result confirms that the -374AA genotype of the RAGE gene promoter is a protective factor against the severity of CAD lesions in type 2 diabetic patients.