As changes in energy expenditure play a role in the pathogenesis of obesity, we asked if adipocyte-specific loss of ANGPTL4 would lead to changes in energy expenditure, oxygen consumption (VO2), carbon dioxide production (VCO2), or respiratory quotient (RQ; VCO2/VO2). The gene discussed is ANGPTL4; the disease is obesity due to melanocortin 4 receptor deficiency.