Alpha Adducin G460T Variant is a Risk Factor for Hypertension in Tunisian Population

Abstract

Background: Adducin is a membrane cytoskeletal protein, consisting of three subunits: α, β, and γ subunits encoded by three different genes (ADD1, ADD2, ADD3). A specific mutation G460T of the α-adducin gene (ADD1) is associated with high renal tubular sodium reabsorption. This mutation is associated with salt sensitivity and may influence the risk of hypertension. In this study, we investigated the relationship between the G460T polymorphism of the ADD1 and essential hypertension (EH) in the Tunisian population.

Methods: The case-controlled study included 280 patients with hypertension and 257 healthy controls. The G460T polymorphism of ADD1 was determined by polymerase chain reaction-restriction fragment length polymorphism analysis method.

Results: In the whole population, the genotypic frequencies of the a-adducin G460T polymorphism in hypertensive and control groups (GG, GT, TT) were 78.6%, 17.5%, 3.9% and 87.5%, 11.29%, 1.16%, respectively (χ2 = 9.13, p < 0.01). The genotype was associated with hypertension, OR = 1.79, 95% CI (1.04 - 3.41), p < 0.03 for GT heterozygous and OR = 1.93, 95% CI (1.39 - 2.22), p < 0.03 for TT homozygous. Moreover, when we stratified the population according to gender, the genotypic frequencies were significantly associated with G460T polymorphism in men (p < 0.01) and in women (p < 0.05). Furthermore, no relationship was found between clinical characteristics and ADD1 G460T genotypes.

Conclusions: The present study shows that the a-adducin G460T polymorphism is associated with EH. Our results suggest that this variant can be considered a genetic risk factor for hypertension in the Tunisian population.