Association ofCLCNKBHaplotypes and Hypertension in Mongolian and Han Populations

Abstract

We investigated a possible association between genetic variations in chloride channel Kb (CLCNKB) gene and essential hypertension (EH) in the Mongolian and Han populations in Inner Mongolia. Our study included 414 unrelated Mongolian herdsmen and 524 Han farmers. Two tagSNPs of CLCNKB (rs945393 and rs10803414) were identified from the Chinese HapMap database based on pairwise r(2) ≥ 0.5 and minor allele frequency ≥0.05. Genotyping was performed using the PCR/ligase detection reaction assay. There was significant difference in allele frequency of rs10803414 between the EH group (35%) and the control group (26%) in the Mongolian population (P < .05). Significant association was identified between rs10803414 and EH in the Mongolian population (P < .05) and rs945393 and EH in the Han population (P < .01). The frequency of haplotype CC in the EH group (9.4%) was significantly higher than in the control group (4.6%) in the Mongolian population; individuals who possessed the CC haplotype had a significantly higher risk of EH in the Mongolian population. There was no association between haplotype and EH in the Han population. After adjusting for age, sex, and other confounding risk factors, only rs10803414 was the risk factor of hypertension in Mongolians. Our results indicate that rs10803414 in CLCNKB confers a significant risk of EH in the Mongolian population and haplotype CC of CLCNKB is a genetic factor for EH in the Mongolian population. Our study expands the association between CLCNKB and EH to a non-European ancestry population and provides the first evidence of a cross-race susceptibility of EH locus.

Association of variants in renal salt reabsorption-related gene SLC12A3 with essential hypertension in a Mongolian population

“…Family aggregation of hypertension in Mongolians suggests that genetic factors might play an important role in the etiology of hypertension in Mongolians. Our previous study confirmed that the chloride channel Kb gene, CLCNKB, and the PPARγ gene are involved in the genetic susceptibility to hypertension in Mongolians (Gao et al, 2010;Su et al, 2012). Furthermore, in a small study of 385 unrelated Mongolians (158 patients with hypertension vs 227 normotensive subjects), we previously examined the association of the SLC12A3 gene with hypertension in Mongolians using nine tagSNPs of the SLC12A3 gene (rs6499858, rs2289119, rs13306673, rs2010501, rs7188995, rs7204044, rs4784733, rs8063406, and rs2304478) (Chang et al, 2011b).…”