The current study’s failure to identify significant associations does not mean that associations do not exist. Although statistically nonsignificant, our top SNP is noteworthy in that the GLP2R, which is a member of the G protein-coupled receptor superfamily, is a receptor for a 33-amino acid proglucagon-derived peptide (GLP2), both expressed primarily in the gut. GLP2 has been shown to slow the ingestion and transit of food through the GI tract [Burrin et al., 2001]. While there is no evidence to suggest that systemic administration of GLP2 is associated with food intake, central administration of GLP2 in the lateral cerebral ventricle has been shown to inhibit food intake in rats [Tang-Christensen et al., 1996; Drucker, 1998]. GLP2 is also related to homeostatic control of human body weight in that GLP2 acts as a neurotransmitter linking the brainstem with the dorsal medial hypothalamic nucleus [Tang-Christensen et al., 2000]. Our second top SNP is associated with the PAH gene which codes for the enzyme phenylalanine hydroxylase [Scriver, 2007]. Phenylalanine hydroxylase is responsible for the conversion of phenylalanine to tyrosine. Phenylalanine is found in
