Interestingly, treatment of the obesity-control animal groups with a CB1 antagonist appeared to mimic the effects of RYGB on energy balance and weight, whereas treatment of the RYGB animal group with a CB1 agonist resulted in greater weight gain in the RYGB-treated group compared with the RYGB-control group. The gene discussed is CNR1; the disease is obesity due to melanocortin 4 receptor deficiency.