Overexpression ↑ diurnal overeating, BW, obesity; associated with elevated circulating leptin and dysfunctional adipocytes with no changes in POMC immunoreactivity; knockdown did not affect basal feeding or weight gain but ↓ fasting-induced hyperphagia and locomotion. The gene discussed is LEP; the disease is obesity due to melanocortin 4 receptor deficiency.