G1359A polymorphism in the cannabinoid receptor-1 gene is associated with the presence of coronary artery disease in patients with type 2 diabetes.

OBJECTIVE

Previous studies demonstrated that G1359A polymorphism of cannabinoid receptor-1 (CNR1) was associated with cardiovascular risk factors including obesity, insulin resistance, dyslipidemia, and inflammation, which are also risk factors for developing type 2 diabetes mellitus (T2DM). Therefore, this study was aimed to determine whether G1359A polymorphism of CNR1 is associated with T2DM and the presence of coronary artery disease (CAD) in patients with T2DM.

METHODS

A total of 450 patients with T2DM (259 patients with CAD and 191 patients without CAD) and 94 healthy subjects were genotyped using polymerase chain reaction and restriction fragment length polymorphism method.

RESULTS

No significant differences in genotype frequency of CNR1 were found between normal controls and patients with T2DM without CAD. GG genotype frequency of CNR1 was significantly higher in the patients with T2DM with CAD compared with those without CAD and healthy subjects (P = 0.003 and P = 0.005, respectively). Unconditional logistic regression analysis revealed that GG genotype was significantly associated with the presence of CAD in the patients with T2DM compared with GA and AA genotypes (odds ratio, 2.632; 95% confidence interval, 1.481-4.678; P < 0.001). In addition, GG genotype of CNR1 was significantly correlated with elevated levels of body mass index, systolic blood pressure, homeostasis model assessment of insulin resistance, and C-reactive protein, as well as decreased levels of high-density lipoprotein cholesterol in patients with T2DM.

CONCLUSIONS

G1359A polymorphism of CNR1 may be not associated with T2DM but may contribute to the genetic risk for the presence of CAD in patients with T2DM of Chinese Han population.