Association of the endothelial nitric oxide synthase (ecNOS) gene polymorphism with carotid atherosclerosis in type 2 diabetes

This study was done to see whether 27-base pair repeats polymorphism in intron 4 of ecNOS gene is associated with carotid atherosclerosis in type 2 diabetic patients. The polymorphism was identified by polymerase chain reaction (PCR). Ultrasound parameters of carotid atherosclerosis were analyzed in relation to the genotype in 210 patients with type 2 diabetes. The ecNOS4a allele was detected in 34 (16.2%) of this study group. With the exception of the plaque count (P = 0.069), all other parameters obtained by ultrasound examination of carotid arteries were significantly correlated with presence of ecNOS4a allele (P < 0.05). As all the measured carotid parameters correlated well each other, we selected the total mean carotid IMT (intima-media thickness) value to be used for this analysis. In the multivariate analysis including several variables such as age, sex, hypertension, LDL cholesterol, waist–hip ratio, and fasting insulin, all determined to be significant by univariate analysis, ecNOS4a allele had a significant correlation with total mean IMT (P < 0.001). In conclusion, the ecNOS4a allele is associated with carotid atherosclerosis in type 2 diabetic patients in Korea.