obsolete thiourea tasting

MONDO:0044248

OBSOLETE. The sense of bitter taste is mediated by a group of bitter taste receptor proteins that reside on the surface of taste cells within the taste buds of the tongue. These proteins are 7-transmembrane domain, G protein-coupled receptors that are encoded by the TAS2R gene family (see TAS2R10; OMIM:604791), which contains at least 25 functional genes ({22:Kim et al., 2005}).nnHumans worldwide display a bimodality in sensitivity to the bitter taste of PTC, with approximately 75% of individuals perceiving it as intensely bitter, whereas the rest perceive it as tasteless. This difference has been the basis of study of taste perception in humans for over 70 years. {21:Kim and Drayna (2004)} provided an historical review of the subject.nnPropylthiouracil (PROP) and PTC are members of a class of compounds known as thioureas. The compounds carry the chemical group N-C=S, which is responsible for their characteristic bitter taste ({3:Bartoshuk et al., 1994}; {10:Drewnowski and Rock, 1995}).