title: Beta2 adrenoceptor functional gene variants, obesity, and blood pressure level interactions in the general population.
abstract: We investigated the association of beta2 adrenoceptor functional gene variants (Arg16Gly, Gln27Glu, and Thr164Ile polymorphisms), obesity phenotypes, and blood pressure levels in a large, ethnically mixed urban population. The individuals (n=1576) were randomly selected for a cross-sectional study of cardiovascular risk factors in Vitória, Brazil. Statistically significant associations among systolic blood pressure and the Arg16Gly and Thr164Ile variants were identified in univariate analysis. The Gly16/Gly16 genotype was still associated with systolic blood pressure (SBP) in multivariate analysis adjusting for age, gender, ethnicity, total cholesterol, diabetes, and body mass index (BMI) (P=0.01). The Arg16 allele was the only genotypic variable associated with BMI, and, in a dominant model, it remained associated with an increased BMI even after adjustment for age, gender, ethnicity, triglycerides, HDL cholesterol, LDL cholesterol, diabetes, and hypertension status (P=0.02). Although the different polymorphisms did not interact in the determination of SBP, a significant interaction with BMI (P=0.02), not through linkage disequilibrium, was identified between the Gln27Glu and the Thr164Ile variants. Furthermore, a significant interaction among the Arg16Gly polymorphism and BMI (P=0.036) and waist-hip ratio (P=0.003) in determining SBP was disclosed by ANOVA factorial modeling, with SBP used as the dependent variable. An interaction between the Thr164Ile polymorphism and waist-hip ratio was also identified (P=0.018). Finally, multiple logistic regression models showed a 1.48-fold increase in the risk of hypertension in individuals harboring the Gly16/Gly16 genotype and a 1.31-fold (P=0.01) and a 1.49-fold (P=0.003) increased risk of obesity in individuals harboring the Gln27/Gln27 genotype or the presence of the Arg16 allele, respectively. Taken together, these data provide evidence for a strong but complex relation between beta-adrenoceptor gene variants, hypertension, and obesity.
authors.affiliation: Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor), São Paulo University Medical School, São Paulo, SP, Brazil.
authors.forename: Alexandre C
authors.initials: AC
authors.lastname: Pereira
authors.forename: Marcilene S
authors.initials: MS
authors.lastname: Floriano
authors.forename: Glória F A
authors.initials: GF
authors.lastname: Mota
authors.forename: Roberto S
authors.initials: RS
authors.lastname: Cunha
authors.forename: Fernando L
authors.initials: FL
authors.lastname: Herkenhoff
authors.forename: José G
authors.initials: JG
authors.lastname: Mill
authors.forename: José E
authors.initials: JE
authors.lastname: Krieger
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000235:genetics*; D003430:Cross-Sectional Studies; D003710:Demography; D005260:Female; D005787:Gene Frequency; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000175:diagnosis / Q000235:genetics*; D010641:Phenotype; D011110:Polymorphism, Genetic; D018343:Receptors, Adrenergic, beta-2 / Q000235:genetics*
chemical_list: D018343:Receptors, Adrenergic, beta-2