Association of Single Nucleotide Polymorphisms in Salt Taste Receptor Genes With Dietary Salt Intake and Blood Pressure Among Iranian Adults Population

Abstract

Objectives So far, few researches has examined how genetic variation in salt taste receptors affects food intake in Iranian population. Thus, in this study, we aimed to investigate associations of single nucleotide polymorphisms (SNPs) in salt taste receptors genes with dietary salt intake and blood pressure. Methods This cross-sectional study was carried out among 116 randomly selected adults aged 18 years and over in Isfahan city, Iran. Subjects with diabetes insipidus, renal insufficiency, a special dietary regimen, fasting or menstruating on the day of sampling, using diuretics and oral contraceptives or pregnant and lactating women as well as participants who had incomplete 24-h urine collection were excluded. A 24-h urine collection and blood pressure measurement were done. Whole blood was collected to extract DNA and measure SNP rs239345 in the ENaC and rs224534, rs4790151 and rs8065080 in the TRPV1 gene. Results Homozygous carriers of the T allele for rs239345 were found to consume significantly more sodium (4414.7 ± 1943.8 mg/day) compared to the AA genotype (3887.4 ± 1709.1 mg/day). Further, they also had higher diastolic blood pressure compared to subjects with the AA genotype (81.3 ± 9.7 vs. 75.3 ± 8.3 mmHg). Compared to subjects with the CC genotype, those with homozygous carriers of the T allele for rs8065080 in the TRPV1 had higher sodium intake (3592.6 ± 1645.2 mg/day vs. 4604.2 ± 2013.5 mg/day) and systolic blood pressure (118.1 ± 11.3 mmHg vs. 123.4 ± 11.5 mmHg). No differences were found in dietary sodium intake and blood pressure with the rs224534 and rs4790151 SNPs. Conclusions These findings suggest that genetic variation in the ENaC and TRPV1 genes may contribute to inter-individual differences in salt intake and blood pressure. Funding Sources The National Institute for Medical Research Development (NIMAD) was funded this study via grant number of 977,549.