C825T polymorphism of the G-protein β3 subunit and its association with essential hypertension in Uzbek males.

OBJECTIVES

We investigated the association between the C825T polymorphism of the G-protein β3 subunit (GNB3) gene with essential hypertension (EH) and cardiovascular remodeling markers in Uzbek males.

STUDY DESIGN

The study included 174 Uzbek men (mean age 49±10 years) with untreated EH of stage 1-2 and 60 normotensive males. The C825T polymorphism of the GNB3 gene in the patient and control groups was determined by polymerase chain reaction. The patients were assessed with blood pressure measurements, ambulatory blood pressure monitoring, body mass index (BMI), carotid artery intima-media thickness (IMT), flow-mediated dilation (FMD) of the brachial artery, echocardiography, and urinary albumin excretion (UAE) level.

RESULTS

The frequencies of the CC, CT, and TT genotypes were 36.8%, 53.5%, and 9.8% in hypertensive men, and 0%, 83.3%, and 16.7% in healthy men, respectively (p=0.0001). The frequencies of the C and T alleles were 63.8% and 36.2% in the hypertensive group, and 41.7% and 58.3% in the control group, respectively (p=0.0001). The CC genotype exhibited a significantly greater risk for hypertension compared to CT and TT genotypes (OR=72.38, 95% CI 4.40-1190.34). The C825 allele showed a higher association with hypertension in comparison to the 825T allele (OR 2.41, 95% CI 1.58-3.68). Compared to patients with the CT+TT genotypes, the CC genotype carriers had significantly higher BMI (p=0.0001), systolic (p=0.0001) and diastolic (p=0.003) blood pressures (SBP/DBP), higher nighttime DBP (p=0.042), a greater nighttime variability in both SBP and DBP (p=0.002), and greater carotid artery IMT (p=0.0001) and UAE (p=0.015) values.

CONCLUSION

Our findings show a significant association between the GNB3/C825T gene polymorphism and EH, with the CC genotype exhibiting higher blood pressure, BMI, and vascular remodeling markers in Uzbek hypertensive men.