G-Protein beta 3 subunit gene (GNB3) polymorphism 825C -> T in patients with hypertensive crisis

Objective: The polymorphism 825C-->T in exon 10 of the gene GNB3 encoding t he beta 3 subunit of heterotrimeric guanine nucleotide binding regulatory p roteins (G-proteins) results in a splicing variant (GNB3-s) in which the nu cleotides 498-620 of exon 9 are deleted. The T allele has been shown to be overrepresented in patients with essential hypertension. Because GNB3-s may support the development of severe elevation of blood pressure, we hypothes ized that GNB3 825C-->T may be present more frequently in patients with hyp ertensive crisis. Design:Case control study. Setting: Department of Emergency Medicine at the University Hospital of Vie nna, Vienna, Austria. Patients: A total of 174 patients admitted to an emergency department for t reatment of hypertensive crisis diagnosed as suffering from essential hyper tension. Interventions: None. Measurements and Main Results:Patients were genotyped for the 825C-->T tran sition in GNB3,An equal number of age- and gender-matched normotensive, hea lthy individuals served as the control population. The allele frequency of 825C-->T in the GNB3 gene was 0.310 in patients with hypertensive crisis an d 0.342 in the control group. There was no difference in genotype distribut ion and allele frequency between the patients and the age- and gender-match ed control group or between the observed prevalence and the occurrence rate expected from the Hardy-Weinberg principle within each group. Conclusions: GNB3 825C-->T is not associated with the phenotype of hyperten sive crisis in patients suffering from essential hypertension. Furthermore, our data do not support the concept that the 825C-->T transition in the GN B3 gene is associated with essential hypertension.