A Meta-Analysis on Polymorphic Trait of Taste Perception Mediated by TAS2R38 Genotype

The objective of this study is to review the association of TAS2R38 polymorphisms and taste phenotypes to bitter compounds (phenylthiocarbamide [PTC]/propylthiouracil [PROP]), and its association among persons who drink alcohol and individuals with smoking behavior. A literature search was carried out in PubMed, ScienceDirect, Cochrane, and Wiley online library databases using the keyword "(Bitter taste receptor genes OR TAS2R38) AND (PROP OR propylthiouracil) AND (PTC OR phenylthiocarbamide)," "(Bitter taste receptor genes OR TAS2R38) AND (alcohol)," "(Bitter taste receptor genes OR TAS2R38) AND (tobacco OR smoker)" to find articles evaluating the association of taste phenotypes and TAS2R38 polymorphisms, and its association among persons who drink alcohol and individuals with smoking behavior. The analysis show that TAS2R38 taster genotype (proline-alanine-valine [PAV] allele) was significantly (OR, 5.88; CI [3.87, 8.95], p < .001) associated with taster phenotype for bitter compounds (PTC/PROP), and TAS2R38 nontaster genotype (alanine-valine-isoleucine allele) was significantly (OR, 6.73; CI [4.57, 9.90], p < .001) associated with nontaster phenotype for bitter compounds. Further, TAS2R38 taster genotypes (PAV homozygotes and heterozygotes) were significantly associated with higher alcohol intake (OR, 5.15; 95% CI [2.66, 9.98]; p < .001) and among individuals with smoking behavior (OR, 1.73; 95% CI [1.24, 2.42]; p = .001). This suggests that TAS2R38 single nucleotide polymorphisms can be identified by clinically assessing taste phenotype status for bitter compounds and can be used as a potential therapeutic target in the prevention and treatment of harmful higher alcohol intake and smoking behavior. Public Health Significance The current evidence suggests that taste genotype status of an individual modifies the risk of higher alcohol intake and smoking behavior. Thus, identifying the taste phenotype status and modifying the expression of taste genes could be a novel therapeutic target in the prevention and treatment of harmful higher alcohol intake and smoking behavior.