title: Rare haplotypes of the gene TAS2R38 confer bitter taste sensitivity in humans.
abstract: BACKGROUND
  The TAS2R38 gene is widely responsible for the well-known bimodal response to a family of bitter chemicals which includes 6-n-propylthiouracial (PROP). There are two common haplotypes of this gene, the recessive AVI and the dominant PAV, both of which are well studied. Conversely, the role of rare TAS2R38 haplotypes on bitter taste sensitivity has been notoriously difficult to study due to small sample sizes. Here we present PROP sensitivity data of 97 individuals that have been observed to carry rare haplotypes (AAV, AAI, PAI, PVI) of the TAS2R38 gene.
  
  
  RESULTS
  Participants rated their bitter taste perception to a PROP filter disc then provided a buccal DNA sample from which the TAS2R38 gene was sequenced and analyzed. We found the prevalence of the PAV haplotype to be 42.3 %, AVI 53.1 %, AAV 2.5 %, AAI 1.2 %, PAI 0.8 % and PVI 0.1 %. We found that the AAI, AAV, and PAI haplotypes present intermediate taste sensitivity.
  
  
  CONCLUSIONS
  These data are further evidence that bitter taste sensitivity to PROP exists as a broad range, and not exclusively as nontasters, medium tasters, and supertasters.
authors.affiliation: Genetics of Taste Lab, Health Sciences Department, Denver Museum of Nature & Science, 2001 Colorado Blvd., Denver, CO 80205 USA ; University of Colorado Denver, 1201 Larimer St., Denver, CO 80204 USA.
authors.forename: Emma E
authors.initials: EE
authors.lastname: Boxer
authors.affiliation: Genetics of Taste Lab, Health Sciences Department, Denver Museum of Nature & Science, 2001 Colorado Blvd., Denver, CO 80205 USA.
authors.forename: Nicole L
authors.initials: NL
authors.lastname: Garneau
keywords: Bitter; PROP; Rare haplotype; SNP; TAS2R38; Taste