Relation between Obesity and Blunted Striatal Response to Food is Moderated by TaqlA1 Gene

The dorsal striatum plays a role in consummatory food reward, and striatal dopamine receptors are reduced in obese relative to lean individuals, suggesting that the striatum and dopaminergic signaling in the striatum may contribute to development of obesity. Thus, we tested whether striatal activation in response to food intake is related to current and future increases in body mass and whether these relations are moderated by presence of the A1 allele of the TaqlA1 gene, which is associated with compromised striatal dopamine signaling. Cross-sectional and prospective data from two functional magnetic resonance imaging studies support these hypotheses, suggesting that individuals may overeat to compensate for a hypofunctioning dorsal striatum, particularly those with genetic polymorphisms thought to attenuate dopamine signaling in this region.