ASSOCIATION OF ARG16GLY POLYMORPHISM OF THE BETA-2 ADRENERGIC RECEPTOR (B2AR) GENE WITH SYSTOLIC HYPERTENSION IN A LATIN-AMERICAN POPULATION FROM COLOMBIA: PP.21.319

Abstract

Objective: Beta-2 adrenergic receptor (B2AR) gene is among the candidate genes most widely studied in hypertension. In particular, Arg16Gly (46 A–>G rs1042713) a non-synonymous coding polymorphism of the B2AR, has been reported to be associated with hypertension with inconclusive results. The aim of the present study was to test the association between this polymorphism and essential hypertension in a Latin American population. Methods: A total of 800 individuals aged 30–65 years were recruited for the study. They constituted a random and representative sample of the general population of the city of Medellin (Colombia). Arg16Gly polymorphism was repeatedly genotyped (forward and backward, genotype accuracy >99%), using automated DNA sequencer 3730XL (ABI Prism). Blood pressure (BP) levels were defined by the average of four conventional sitting BP measurements (2007 ESH-ESC Guidelines) made at five min intervals by two trained physicians. All measurements were performed in the left arm at the heart level after 5 min rest using a standard mercury sphygmomanometer. Systolic hypertension was defined as a systolic (S)BP at or above 140 mmHg. Results: Allelic distribution of the Arg16Gly polymorphism was in Hardy-Weinberg equilibrium. In the logistic regression analysis, systolic hypertension was considered as the dependent variable and only individuals not under antihypertensive treatment were included (n = 599). After adjustment for age, sex, diabetes, BMI and smoking (independent variables), individuals homozygous for Gly16 (Gly/Gly genotype) had a higher significant risk of systolic hypertension (89% increase in odds of having systolic hypertension) when compared to the individuals with other genotypes (Arg/Arg or Arg/Gly) [odds ratio (OR) = 1.89; 95% confidence interval (CI) = 1.18–3.03; p = 0.008]. See table Conclusions: These results support the hypothesis that polymorphisms in the ADRB2 gene are involved in the modulation of blood pressure levels in humans. In particular, the presence of a Glycine homozygous genotype of the Arg16Gly polymorphism is associated with an increased risk of systolic hypertension in subjects of Latin-American origin.