Personalized expression of bitter ‘taste’ receptors in human skin

The skin and the taste system both function to protect the human body and are a first point of contact with poisons and pathogens. These systems may share a similar protective mechanism because both human taste and skin cells express mRNA for bitter 9taste9 receptors (T2Rs). Here we used gene-specific methods to measure mRNA from all known bitter receptor genes in adult human skin from freshly biopsied samples and from samples collected at autopsy from the Genotype-Tissue Expression project. Human skin expressed some but not all T2Rs, and for those that were expressed, the relative amounts differed markedly among individuals. For the most highly expressed T2Rs, mRNA abundance was related to presumed sun exposure (TAS2R5 and TAS2R14), sex (TAS2R4 and TAS2R5), and age (TAS2R5), although these effects were not large. These findings contribute to our understanding of extra-oral expression of chemosensory receptors.