Clinical Trial: Gustin Gene Polymorphism and 6-n-propylthiouracil (PROP) Taste

Study Status: Completed
Recruit Status: Completed
Study Type: Observational

Official Title: Sensitivity to 6-n-propylthiouracil (PROP) Association With Gustin (CA6) Gene Polymorphism, Salivary Zinc and BMI in Humans

Brief Summary: The investigators evaluate the possible association of PROP taste with gustin gene polymorphism rs2274333 (A/G), salivary zinc ion concentration and BMI. In addition, it has also been evaluated PROP taste sensitivity by recording monophasic potentials from the tongue.

Detailed Summary:

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.


Sponsor: University of Cagliari

Current Primary Outcome: 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.



Original Primary Outcome: Association Between Gustin Gene Polymorphism and PROP Sensitivity [ Time Frame: 7 months ]

Current Secondary Outcome:

  • 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.


Original Secondary Outcome: association between PROP sensitivity, Saliva zinc ion concentration and BMI [ Time Frame: 7 months ]

Information By: University of Cagliari

Dates:
Date Received: April 1, 2010
Date Started: October 2009
Date Completion:
Last Updated: December 21, 2016
Last Verified: October 2016