Gustin Gene Polymorphism and 6-n-propylthiouracil (PROP) Taste (gustinprop)
|Study Design:||Observational Model: Cohort
Time Perspective: Prospective
|Official Title:||Sensitivity to 6-n-propylthiouracil (PROP) Association With Gustin (CA6) Gene Polymorphism, Salivary Zinc and BMI in Humans|
- Association Between Gustin Gene Polymorphism and PROP Sensitivity [ Time Frame: 7 months ]
We examine associations between PROP status and the polymorphism rs2274333 (A/G) of the gene that codify for the salivary protein, gustin/CA6, Which has been suggested as a trophic factor that promotes growth and development of taste buds by acting on taste bud stem cells.
The intensity of taste perception evoked by PROP and NaCl solutions was estimated to evaluate PROP taster status and molecular analysis of the gustin gene polymorphism was performed in individuals classified by PROP status using PCR techniques.
- Association Between PROP Sensitivity and Saliva Zinc Ion Concentration [ Time Frame: 7 months ]Since the enzymatic function of gustin (CA6) depends upon the presence of Zn at its active site we measured the salivary zinc ion concentration in subjects classified as super-taster, medium taster and non-taster.The salivary Zn2+ concentration was measured with a QuantiChromTM zinc Assay kit (Gentaur, Brussels, Belgium) where the color intensity is directly proportional to the Zn2+ concentration in the sample.
- Electrophysiological Recordings From the Tongue for the Objective Evaluation of Individual Variations of 6-n-propylthiouracil (PROP) Sensitivity [ Time Frame: 1 year ]electrophysiological recordings from the tongue of 43 subjects classified for their taste sensitivity to 6-n- propyltiouracil (PROP) and genotyped for the specific receptor gene, TAS2R38. Density of fungiform papillae was also determined in each subject. The biopotentials were recorded by means of differential electrophysiological derivations between two silver electrodes, one in contact with the ventral surface of the tongue and one in perfect adhesion with the dorsal surface.
- Association Between PROP Sensitivity and BMI [ Time Frame: 7 months ]Since individual ability to taste PROP may be correlated with BMI, we determined BMI (kg/m^2) in subjects classified as super-taster, medium taster and non-taster.Weight (kg) and height (m) were recorded for each subject.
- Taste Perception of Sweet, Sour, Salty, Bitter and Umami and Changes Due to L-Arginine Supplementation, as a Functin of Genetic Ability to Taste PROP. [ Time Frame: 8 months ]Taste perception was assessed by testing the ability to recognize, and the responsiveness to, representative solutions of the five taste qualities, also when supplemented with L-Arg, in subjects classified as PROP-tasters.
Biospecimen Retention: Samples With DNA
|Study Start Date:||October 2009|
|Study Completion Date:||June 2016|
|Primary Completion Date:||December 2009 (Final data collection date for primary outcome measure)|
PROP taste sensitivity
PROP Sensitive and non sensitive individuals are defined as "Tasters" and "Non-tasters", respectively. Taster are further divided in "Super-taster" who perceived PROP as extremely bitter and "Medium tasters" who perceived PROP as moderately bitter.
The investigators evaluate the possible association of PROP taste with gustin gene polymorphism rs2274333 (A/G), salivary zinc ion concentration and BMI.
Furthermore, we apply direct measures of the gustatory system activation following stimulation with PROP, obtained by electrophysiological recordings from the tongue of subjects classified for taster status, genotyped for the specific receptor gene (TAS2R38), and in which papilla density was determined.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01097915
|Sezione di Farmacologia Clinica del Dipartimento di Neuroscienze, San Giovanni di Dio Azienda Ospedaliero Universitaria di Cagliari|
|Cagliari, Ca, Italy, 09124|
|Principal Investigator:||Iole Tomassini Barbarossa, PhD||Dipartimento di Biologia Sperimentale Sezione di Fisiologia Generale Università di Cagliari|