Objective: G protein is one of the most important regulators of intracellular signaling pathways. C825T polymorphism of G protein b3 subunit is associated with increased intracellular signal transduction. The 825T allele has been found associated with a variety of cardiovascular risk factors, including hypertension. The aim of the present study was to investigate the association between the C825T polymorphism of the G protein b3 subunit and essential hypertension in Turkish population.
Methods: This cross-sectional, case-controlled study included 209 patients with essential hypertension (Patient group) and 82 subjects with normal blood pressure (Control group). The G protein b3 subunit C825T gene polymorphism was determined by polymerase chain reaction. Hypertension was defined according to JNC VII criteria. Statistical analysis was performed using Chi square and unpaired t tests. Logistic regression analysis was used to study association between hypertension and genotypes.
Results: We found that the frequencies of the G protein b3 subunit C825T polymorphism in hypertensive and control groups were 17.7%, 59.3%, 23.0% and 32.9%, 48.8%, 18.3%, (CC, CT, TT) respectively (chi2=7.963, p=0.019). In the multivariate logistic regression analysis CT genotype had 2.2 (OR=2.262, 95% CI 1.228-4.167, p=0.009), and TT genotype had 2.3 times (OR=2.335, 95% CI 1.089-5.008, p=0.029) greater risk of hypertension compared to CC genotype.
Conclusion: It seems that the G protein b3 subunit C825T gene polymorphism is associated with systolic and diastolic blood pressure. Furthermore, the study indicates that the G protein b3 subunit may be a susceptible gene to essential hypertension.