Notwithstanding the limitations described, the results we present here are consistent with a nonlinear moderating effect of dopamine function on neural responses [112, 113], such that low predicted DRD4 expression in prefrontal cortex was associated with a more plastic phenotype, conferring obesity risk in more adverse environments, and obesity protection in predominantly favorable environments. This evidence concerns the gene DRD4 and obesity due to melanocortin 4 receptor deficiency.