Taste receptor polymorphisms and longevity: a systematic review and meta-analysis

Abstract

Bitter taste receptors (TAS2R) are involved in a variety of non-tasting physiological processes, including immune-inflammatory ones. Therefore, their genetic variations might influence various traits. In particular, in different populations of South Italy (Calabria, Cilento, and Sardinia), polymorphisms of TAS2R16 and TAS238 have been analysed in association with longevity with inconsistent results. A meta-analytic approach to quantitatively synthesize the possible effect of the previous variants and, possibly, to reconcile the inconsistencies has been used in the present paper. TAS2R38 variants in the Cilento population were also analysed for their possible association with longevity and the obtained data have been included in the relative meta-analysis. In population from Cilento no association was found between TAS2R38 and longevity, and no association was observed as well, performing the meta-analysis with data of the other studies. Concerning TAS2R16 gene, instead, the genotype associated with longevity in the Calabria population maintained its significance in the meta-analysis with data from Cilento population, that, alone, were not significant in the previously published study. In conclusion, our results suggest that TAS2R16 genotype variant is associated with longevity in South Italy.

G protein-coupled receptors that influence lifespan of human and animal models

“…Evidence has been presented that people who have a pair of functional alleles (PAV/ PAV) in the taste receptor type 2 member 38 (TAS2R38) gene may have a favorable genetic status compared to people with non-functional alleles (AVI/ AVI) to achieve greater longevity (Melis et al 2019). Something similar was found with the single nucleotide polymorphism (SNP) rs978739 in taste receptor type 2 member 16 (TAS2R16), where the frequency of the homozygous A/A allele is higher in centenarians than the G/G allele (Campa et al 2012;Malovini et al 2019;Di Bona et al 2020). In both cases, the increase in longevity could be due to a better recognition of the beneficial and harmful molecules that would guide the diet in a better direction such as the consumption of less fat, but also participate in other physiological functions such as efficient immune response and favorable body composition, among other things (Tepper et al 2008;Lee and Cohen 2015;Smail 2019).…”

Demographic history was a formative mechanism of the genetic structure for the taste receptor TAS2R16 in human populations inhabiting Africa's Sahel/Savannah Belt

“…We are aware that this conclusion is challenged by the fact that TAS2R16 is a pleiotropic gene (An & Liggett, 2018; Di Bona et al, 2020; Grassin‐Delyle et al, 2019). Indeed, bitter taste receptors (TAS2R, including TAS2R16) are expressed in several tissues besides the tongue and have been shown to be involved in several distinct functions in the organism outside the gustatory system.…”

“…Indeed, bitter taste receptors (TAS2R, including TAS2R16) are expressed in several tissues besides the tongue and have been shown to be involved in several distinct functions in the organism outside the gustatory system. Considering their role in antimicrobial immune and immune‐inflammatory processes it has been suggested that some mutations might be associated with longevity; in particular variant rs978739 on TAS2R16 (Campa et al, 2012), although this association is currently discussed (Di Bona et al, 2020; Malovini et al, 2019). Moreover, to the best of our knowledge, TAS2R16 variants' association with longevity has only been tested in a few populations from southern Italy, and there is no similar study focused on other European or African populations.…”

“…However, pseudogenization is a complex process (Antinucci & Risso, 2017; Risso et al, 2014) and one has to consider other possible functions of a given gene. This is particularly the case for TAS2R genes and their pleiotropic functions (Bloxham et al, 2020; Di Bona et al, 2020). TAS2R proteins have been detected in a large number of tissues and cells such as neutrophils, hence underlining their role in the innate immune system.…”

“…Indeed, bitter taste receptors (TAS2R, including TAS2R16) are expressed in several tissues besides the tongue and have been shown to be involved in several distinct functions in the organism outside the gustatory system. Considering their role in antimicrobial immune and immune-inflammatory processes it has been suggested that some mutations might be associated with longevity; in particular variant rs978739 on TAS2R16 (Campa et al, 2012), although this association is currently discussed (Di Bona et al, 2020;Malovini et al, 2019) We were aiming to reveal whether the TAS2R16 gene has been under recent selective pressure and compare these results with what is known from environmental and archeological data in this region, and to characterize the factors shaping genetic diversity of human populations. We show that there is no clear signal of positive selection in the TAS2R16 gene in contemporary Sahelian populations, be it among pastoralists or farmers.…”