Association of dopamine receptor D4 (DRD4) gene polymorphism with cardiovascular disease risk factors

Abstract

Dopamine receptor genes are known to be candidate genes, mutations of which may be involved in the development of cardiovascular diseases. The human D4 receptor gene (DRD4) contains a variable number (two to ten copies) of tandem 48-bp repeats in exon 3. The goal of the study was to analyze the association of DRD4 gene polymorphism with cardiovascular disease risk factors in the Russian population: blood pressure (BP), high-density (HDL) and low-density (LDL) lipoprotein cholesterol levels, and the triglyceride level. We genotyped 257 women and 425 men for variable number tandem repeat polymorphism in DRD4. The subjects were Novosibirsk residents of Slavic ethnicity. They were divided either into 7+ (those having the allele of seven or eight repeats) and 7–(two to six repeats) groups or into 2+5+ (two or five repeats) and 2–5–(three, four, six, seven, or eight repeats) groups. We found associations between the 7+ allele and elevated systolic and diastolic BP in women but not in men. Neither sex showed associations between the long variants of the DRD4 gene and pulse blood pressure. The presence of the 2–or 5–allele of the DRD4 polymorphism was associated with low HDL cholesterol levels in women and low total cholesterol levels in men. The polymorphism exerted no significant effects on LDL, HDL, or triglyceride levels in men.