Healthy volunteers
Accepted
Inclusion Criteria:
* Key inclusion criteria include age 18-40 years; English speaking, and good health at the time of study participation.
Exclusion Criteria:
* Key exclusion criteria include cigarette smoking, which alters taste perception, oral disease and subjects undergoing Coumadin therapy. Subjects showing signs of oral disease, including tongue lesions or xerostomia will be excluded from tongue biopsy and therefore excluded from the study. Subjects undergoing Coumadin therapy will be excluded from tongue biopsy due to the risk of bleeding, and therefore excluded from the study. Subjects will not be excluded because of economic status, gender, race or ethnicity.
