Novel genetic variations associated with salt sensitivity in the Korean population.

Salt sensitivity is a risk factor for cardiovascular morbidity and mortality. To date, only a few genetic variations have been identified as being associated with salt sensitivity. This study aimed to estimate the prevalence of salt sensitivity in the Korean population and to identify genetic variants affecting its development. A total of 101 Korean participants consumed a low-salt diet for 7 days followed by a high-salt diet for 7 additional days. Salt sensitivity was determined by noting any significant elevation in the 24-h mean arterial blood pressure. To determine genetic variants affecting salt sensitivity, 36 single-nucleotide polymorphisms (SNPs) that were previously reported to be associated with hypertension were tested for any associations with salt sensitivity. Of the 101 subjects, 28 (27.7%) were determined to have salt sensitivity. Out of the 36 SNPs tested, four were significantly associated with salt sensitivity after adjusting for confounding factors: rs2681472 in ATPase, Ca(++) transporting, plasma membrane 1 (ATP2B1), rs7961152 in branched chain aminotransferase 1 (BCAT1), rs16998073 in fibroblast growth factor 5 (FGF5) and rs2398162 in LOC100132798. For rs3754777 in serine threonine kinase 39 (STK39) and rs1937506, associations with salt sensitivity were observed before adjusting for confounding factors. Haplotype analysis revealed that the A-C haplotype of rs3754777-rs6749447 in STK39 was more frequent in the salt-sensitive group compared with the salt-resistant group, and was associated with salt sensitivity. This study estimates the prevalence of salt sensitivity in the Korean population and demonstrates a novel association between salt sensitivity and the ATP2B1, BCAT1, FGF5, LOC100132798 and STK39 genetic variations.