The Role of G Protein β3 Subunit Polymorphisms C825T, C1429T, and G5177A in Turkish Subjects with Essential Hypertension

Abstract

Hypertension is a multifactorial disorder that constitutes a major risk factor for the cardiovascular system. Heterotrimeric G-proteins, which couple receptors for diverse extracellular enzymes or ion channels, are correlated with disease mechanisms. Several studies have demonstrated an association between G protein polymorphisms and essential hypertension in some populations, although contradictive results also exist. In this study, we have investigated the potential role of the C825T, C1429T, and G5177A polymorphisms of the β3 subunit of G-proteins in essential hypertension in a group of Turkish subjects. Genomic DNA from 106 normotensive individuals (117.4 ± 13.1, 75.2 ± 10.5; systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels, respectively) and 101 hypertensive subjects (152.3 ± 18.0, 92.5 ± 11.6; SBP and DBP levels, respectively) were studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing methods for these polymorphisms. Allele frequencies of the polymorphisms were consistent with Hardy Weinberg equilibrium, except for the C825T polymorphism (χ(2) = 7.8). The frequencies of the 825T and 1429T variants were higher in hypertensive subjects compared to those of controls. Differences between hypertensives and controls were not statistically significant, though difference was very close to significance for C825T (p = 0.056 and 0.099 for 825T and 1429T, respectively). T allele frequency in overall population showed significant association with hypertension for C825T (0.0134). The prevalence of the 5177A-variant was very low and all subjects carrying it were heterozygotes in both groups.

The dominant models of KCNJ11 E23K and KCNMB1 E65K are associated with essential hypertension (EH) in Asian

“…Essential hypertension (EH), characterized by significant and persistent elevations in arterial pressure, is a multifactorial disorder, involving an interaction of genetic, lifestyle, and environmental factors. [1,2] The etiology and pathophysiology of EH may refer to vascular inflammation and endothelial dysfunction. [3,4] Although multiple studies have provided evidence of the role of genes in the determination of blood pressure levels and hypertension, [5,6] the identities of the contributing genes remain controversial.…”