Dopamine D2 Receptor Genotype (C957T) and Habitual Consumption of Sugars in a Free-Living Population of Men and Women

BACKGROUND/AIMS: The dopamine D2 receptor (DRD2) has been implicated in modulating the rewarding effects of foods high in sugar. The purpose of this study was to determine whether a variation in the DRD2 gene affects habitual consumption of sugars in a free-living population. METHODS: Caucasian men (n = 96) and women (n = 217) 20-29 years of age completed a 1-month food frequency questionnaire and were genotyped for the C957T polymorphism in the DRD2 gene. Analyses of covariance with post-hoc Tukey tests were used to compare nutrient intakes between genotypes adjusting for potential confounders. RESULTS: Among men, consumption of sucrose was 60 +/- 6, 48 +/- 4, and 39 +/- 5 g/day for those with the CC, CT and TT genotypes, respectively, with a significant difference between the homozygotes (p = 0.03), suggesting an additive mode of inheritance. Among women, sucrose consumption was 42 +/- 4, 53 +/- 2, and 44 +/- 4 g/day for the CC, CT and TT genotypes, respectively, with CC and CT differing significantly (p = 0.02), suggesting a partial heterosis mode of inheritance. No differences were observed for protein or fat. CONCLUSIONS: These findings suggest that genetic variation in DRD2 influences food selection and may explain some of the interindividual differences in sugar consumption.