Detection of genetic variations of regulator of G-protein signaling 2 in hypertensives by sequencing.

Objective: To investigate the new genetic variations of regulator of G-protein signalling 2 (RGS2) gene in Kazakh hypertensives.

Methods: Totally 94 Kazakh patients with essential hypertension were enrolled and genomic DNA was extracted from their peripheral blood leukocytes. All the exon regions and their flanking sequences of RGS2 were directly sequenced.

Results: We identified 13 variants including 5 common- single nucleotide polymorphisms with a minor allele frequency over 5%single nucleotide polymorphisms and 8 novel variations in 94 Kazakh hypertensives. Among these variations, 2 were in the introns and 7 in the promoter region. One subject had a G-to-C substitution at nucleotide 54 in exon 1, which lead to an amino acid substitution from K-to-N at position 18; another individual had an A-to-G substitution at nucleotide 2422 in exon 5, resulting in an amino acid from Y-to-C at position 178. Among eight common single nucleotide polymorphisms, -638A>G, -395G>C, 1891-1892TC I/D, and 2971G>C,and -43A>T and 2297A>G were in tight linkage disequilibrium with an r-square of more than 0.8, respectively.

Conclusions: The variants and their frequencies in RGS2 gene in Kazakh hypertensives may have ethnic differences when compared with other populations. The frequencies of the mutations are low in this population, and whether they influence blood pressure regulation requires further functional experiments.