Sour Taste SNP KCNJ2-rs236514 and Differences in Nutrient Intakes and Metabolic Health Markers in the Elderly

Celeste Ferraris; Alexandria Turner; Christopher J Scarlett; Martin Veysey; Mark Lucock; Tamara Bucher; Emma L Beckett

doi:10.3389/fnut.2021.701588

Sour Taste SNP KCNJ2-rs236514 and Differences in Nutrient Intakes and Metabolic Health Markers in the Elderly

Front Nutr. 2021 Aug 17:8:701588. doi: 10.3389/fnut.2021.701588. eCollection 2021.

Authors

Celeste Ferraris¹, Alexandria Turner¹, Christopher J Scarlett¹, Martin Veysey^{2

3}, Mark Lucock¹, Tamara Bucher^{1

4

5}, Emma L Beckett^{1

4

5}

Affiliations

¹ School of Environmental and Life Sciences, The University of Newcastle, Ourimbah, NSW, Australia.
² School of Medicine & Public Health, The University of Newcastle, Gosford, NSW, Australia.
³ Hull York Medical School, University of Hull, Cottingham, United Kingdom.
⁴ Priority Research Centre for Physical Activity and Nutrition, The University of Newcastle, Callaghan, NSW, Australia.
⁵ Hunter Medical Research Institute, Newcastle, NSW, Australia.

Abstract

Single nucleotide polymorphisms (SNPs) in taste receptors influence dietary choices that contribute to health and quality of life. Individual differences in sour taste perception and preference have been linked to heritable genetics, yet the impact of sour taste receptor SNPs on sour taste is under-researched, and studies on sour taste SNP associations to diet and health are lacking. Therefore, this study explored the relationships between the sour taste SNP KCNJ2-rs236514 and estimated macronutrient, vitamin and mineral intakes, and markers of metabolic health. Associations were explored in 523 participants aged 65 years and older with data analysed using standard least squares and nominal logistic regression modelling with post hoc student's t-tests and Tukey's HSD. Associations were found between the presence of the KCNJ2-rs236514 variant allele (A) and lower intakes of energy, total fat, monounsaturated fat and saturated fat. The lower fat intakes were significant in female carriers of the variant allele (A), along with lower water intake. Lower retinol, riboflavin, folate, calcium and sodium intakes were found in the KCNJ2-A allele carriers. In females, the variant allele was associated with lower sodium intake before and after Bonferroni adjustment. Higher body mass index, waist and waist-to-hip ratio measures were found in males carrying the variant allele. Lower levels of liver function biomarkers were associated with the presence of the KCNJ2-A allele. Overall and in males, the variant's association to lower gamma-glutamyl transferase (GGT) levels remained significant after Bonferroni adjustments. These novel findings suggest the sour taste SNP, KCNJ2-rs236514, may be modifying macronutrient, vitamin and mineral intakes, and markers of metabolic health. Research on the extra-oral functions of this SNP may improve health outcomes for those with overweight, obesity and liver disease.

Keywords: KCNJ2; genetics; macronutrient; metabolic; mineral; sour; taste; vitamin.