title: Validation of edible taste strips for identifying PROP taste recognition thresholds.
abstract: OBJECTIVE
  The purpose of this study was to validate the use of edible taste strips for measuring taste recognition thresholds for the bitter-tasting compound 6-n-propylthiouracil (PROP).
  
  
  METHODS
  Taste recognition thresholds for PROP were obtained by two separate methods. Thresholds were also identified in subjects whose airflow through the nose was blocked. Threshold values were then compared to genotype analysis of the TAS2R38 taste receptor, which is the major determinant for the detection of PROP.
  
  
  METHODS
  Edible taste strips were used to examine taste recognition thresholds for PROP. Thresholds were determined by the method of ascending limits and by the method of reversals. Single nucleotide polymorphism analysis of the TAS2R38 gene was used to identify PROP taster status.
  
  
  RESULTS
  Taste recognition thresholds for PROP formed two distributions. Thresholds for one group varied from 4 to 219 nmol and represented PROP tasters. The second group could not detect the bitter taste of PROP at ≤800 nmol and represented PROP nontasters. The method of ascending limits and the method of reversals yielded similar threshold results. The expression of a PAV allele permitted detection of PROP, but AVI homozygotes could not detect the bitter taste of PROP.
  
  
  CONCLUSIONS
  Edible taste strips were successfully used to detect PROP thresholds at values equal to or lower than those obtained in previous studies using PROP solutions or PROP-impregnated filter papers. This study provides validity evidence for the use of edible taste strips for identifying PROP in the human population.
authors.affiliation: Department of Biology, Temple University, Philadelphia, Pennsylvania 19122, USA.
authors.forename: Hetvi
authors.initials: H
authors.lastname: Desai
authors.forename: Gregory
authors.initials: G
authors.lastname: Smutzer
authors.forename: Susan E
authors.initials: SE
authors.lastname: Coldwell
authors.forename: James W
authors.initials: JW
authors.lastname: Griffith
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005518:Food Preferences / Q000502:physiology; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D043562:Receptors, G-Protein-Coupled / Q000235:genetics; D013652:Taste Threshold / Q000235:genetics / Q000502:physiology*; D014498:Uracil / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D055815:Young Adult; D000098706:Taste Receptors, Type 2
chemical_list: D043562:Receptors, G-Protein-Coupled; D000098706:Taste Receptors, Type 2; C056698:6-n-propyluracil; D014498:Uracil