This gene encodes a member of a family of candidate taste receptors that are members of the G protein-coupled receptor superfamily and that are specifically expressed by taste receptor cells of the tongue and palate epithelia. These apparently intronless genes encode a 7-transmembrane receptor protein, functioning as a bitter taste receptor. This gene is clustered with another 3 candidate taste receptor genes in chromosome 7 and is genetically linked to loci that influence bitter perception.[7] The geographic distribution of TAS2R4 and TAS2R5 missense allele variants which prevent expression of the receptors is aligned with the distributions of tannin sorghum and the destructive agricultural bird pest in Africa, indicating the role of human taste in developing agroecosystems fitting local environments.[8]
Ueda T, Ugawa S, Ishida Y, Shibata Y, Murakami S, Shimada S (July 2001). "Identification of coding single-nucleotide polymorphisms in human taste receptor genes involving bitter tasting". Biochemical and Biophysical Research Communications. 285 (1): 147–51. doi:10.1006/bbrc.2001.5136. PMID11437385.