The Glu27 allele of the beta2 adrenergic receptor increases the risk of cardiac hypertrophy in hypertension.
OBJECTIVE
Cardiac and vascular remodeling occur in response to hypertension. Genetic background appears to modify the development of target organ damage (TOD). We evaluated the impact on hypertension-associated TOD of a highly polymorphic gene with elevated significance for the regulation of the cardiovascular system, the beta2AR gene.


METHODS
We recruited 775 hypertensives (mean +/- SE: age 53.5 +/- 0.5, from 20 to 84 years; female 32.7%; systolic (SBP)/diastolic (DBP) blood pressure: 159 +/- 1.2/101 +/- 0.6 mmHg) referred to the departmental outpatient clinic and screened them for the Arg16Gly, Gln27Glu, and Ile164Thr variants of beta2AR gene. We performed association analyses on clinical, anamnesis, anthropometrical and biochemical parameters as well as cardiac and vascular ultrasound.


RESULTS
We found that the three polymorphisms did not affect blood pressure levels. Cardiac TOD appeared to be related to the Glu27 variant. In fact, the Glu27 allele associates with a 1.4-fold higher risk of developing cardiac hypertrophy, and directly correlated with larger systolic and diastolic left ventricle internal diameters. Vascular TOD was not affected by the three polymorphisms. Ancillary to our finding we observed that the Glu27 variant is associated with a higher incidence of dyslipidemia.


CONCLUSIONS
Our data indicate that beta2AR gene polymorphisms participate in the determination of cardiac TOD associated with hypertension.
Department of Medicina Clinica, Scienze Cardiovascolari ed Immunologiche, Federico II University, Naples, Italy.
Guido
G
Iaccarino
Francesca
F
Lanni
Ersilia
E
Cipolletta
Valentina
V
Trimarco
Raffaele
R
Izzo
Gianni Luigi
GL
Iovino
Nicola
N
De Luca
Bruno
B
Trimarco
D000293:Adolescent; D000328:Adult; D000368:Aged; D006332:Cardiomegaly / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology; D005838:Genotype; D006801:Humans; D006949:Hyperlipidemias / Q000453:epidemiology / Q000235:genetics; D006973:Hypertension / Q000453:epidemiology* / Q000235:genetics*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D018343:Receptors, Adrenergic, beta-2 / Q000235:genetics*; D012307:Risk Factors; D014463:Ultrasonography
D018343:Receptors, Adrenergic, beta-2