Taste Genetics and Oral Health Symptoms in the Canadian Longitudinal Study on Aging

Bitter taste receptors (T2Rs) contribute to innate immune responses and taste preferences. Variants in T2R genes (TAS2Rs) may increase the risk of adverse oral health. This study investigated the association of single nucleotide polymorphisms (SNPs) in 25 TAS2R genes and 12 TAS2R pseudogenes with oral health symptoms within the Canadian Longitudinal Study on Aging (CLSA) cohort. Allele frequencies were calculated using PLINK and compared with the 1000 Genomes Project for individuals of European descent. Associations of oral health symptoms reported by 21,991 individuals (mean age 63 years, 50% female, 48% never smokers), with TAS2R SNPs (87 in TAS2R genes; 37 in TAS2R pseudogenes; minor allele frequency > 0.01) were tested by Chi-square with Bonferroni correction and by logistic regression correcting for sociodemographic variables and oral health habits. Fifteen SNPs in TAS2R8, 9, 13, 14, 20, and 50 showed modest suggestive associations with self-reported sore jaw muscles. These variants were associated with relatively small changes in the odds of reporting sore jaw muscles (6 positive; 9 negative). Nine of these SNPs were in TAS2R20 and highly correlated (r² ≈ 1), likely representing a single locus-level genetic signal. However, none of the associations remained significant after Benjamini-Hochberg FDR correction across all 2604 SNP-phenotype tests, and these findings should therefore be considered exploratory. Structure-function analysis identified selected TAS2R20 residues near the predicted ligand-binding region, providing hypotheses for future functional investigation. These exploratory findings provide hypotheses for future genetic and functional investigation and require independent replication in clinically characterized cohorts.