Association of alpha1a-adrenergic receptor polymorphism and blood pressure phenotypes in the Brazilian population

A total of 1568 individuals were randomly selected from the general population of the Vitória City metropolitan area. Genetic analysis of the Arg347Cys polymorphism was conducted by polymerase chain reaction/restriction fragment length polymorphism. We have compared cardiovascular risk variables and genotypes using ANOVA, and Chi-square test for univariate comparisons and logistic regression for multivariate comparisons.Association analysis indicated a significant difference between genotype groups with respect to diastolic blood pressure (p = 0.04), but not systolic blood pressure (p = 0.12). In addition, presence of the Cys/Cys genotype was marginally associated with hypertension in our population (p = 0.06). Significant interaction effects were observed between the studied genetic variant, age and physical activity. Presence of the Cys/Cys genotype was associated with hypertension only in individuals with regular physical activity (odds ratio = 1.86; p = 0.03) or younger than 45 years (odds ratio = 1.27; p = 0.04).Physical activity and age may potentially play a role by disclosing the effects of the Cys allele on blood pressure. According to our data it is possible that the Arg347Cys polymorphism can be used as a biomarker to disease risk in a selected group of individuals.Increased blood pressure constitutes a major risk factor for cardiovascular diseases, including kidney and cerebrovascular diseases[1,2]. Although the underlying molecular mechanisms remain largely elusive, it is well known that blood pressure is tightly regulated through a net of complex interrelationships between several physiological systems[3]. In addition, several well-designed studies have provided strong evidence that blood pressure variability is largely determined by genetic factors[4,5].The alpha1A-adrenergic receptor (α1A-AR) regulates the cardiac and peripheral vascular system through sympathetic activation. Because of this characteristic, the α1A-AR is considered an important parti