FTO and obesity due to melanocortin 4 receptor deficiency: In line with this idea, children with the FTO polymorphism associated with obesity risk had stronger responses to food commercials in the nucleus accumbens, a reward-related brain region,44 and they were more likely to consume excess calories.45 Physical activity suppresses the effect of obesity-related genes on BMI, perhaps also via appetitive and reward-related pathways.46,47 Future research should directly examine whether the home environment moderates genetic influence on BMI using a genetic risk score, because BMI is a highly polygenic trait.48,49