The purpose of this study is to determine the effect of common human variants in in taste related genes, such as CD36 gene, a putative fat taste receptor, affect fat taste perception.

At present, the general agreement is that humans perceive five taste qualities: sweet, sour, bitter, salty and umami (the savory, meaty taste of some amino acids). It is believed that these qualities evolved to help us find nutrients (e.g. sweets, umami signaled calories) and avoid potential harmful substances (e.g. bitter signalized poison). Despite the fact that some fats, which can only be obtained through the diet, are essential for life, fat is not considered a basic taste; and, the issue of how fats are precisely sensed is unresolved. However, increasing evidence suggests that, in addition to smell and texture, taste plays an important role in fat perception. Putative fat taste receptor classes have been identified in animal models. One such receptor is the glycoprotein CD36, previously documented to be involved in trafficking and storage of fat. CD36 was recently found in rodents' and humans' taste buds. In rodents, CD36 deletion blunts specifically fat recognition. Although CD36 variants are frequent in humans, its role in humans' fat taste perception and preferences remains incompletely understood and will be the focus of the current proposal. The main goal of this study is to determine the effect of a common human variant in the CD36 gene on fat taste perception by using standardized sensory evaluation techniques. In addition, we will examine whether common variants in taste related genes (other than CD36) are associated with individual differences in the perception of flavors of milkshakes prepared with different amounts of fats.

Inclusion Criteria:

• BMI >18-<25 kg/m2 or BMI>29.9 kg/m2.
• 21 to 50 years of age

Exclusion Criteria:

• Previous malabsorptive or restrictive gastrointestinal surgery
• Smoking
• Pregnancy or breastfeeding
• Diabetes
• Taking medication that might affect taste perception

Subjects will be men and women, 21 to 50 yrs of age of all races and ethnic groups. The two groups (i.e. groups with different CD36 genetic variants) will be matched as closely as possible in age, sex, body mass index and race distributions. Subject population will consist of lean subjects (BMI >18-<25 kg/m2) and subjects with obesity (BMI >29.9 kg/m2).