There is an increase in food intake in Pomc−/−Tg+ compared with global Pomc nulls, the metabolic rate is decreased as indicated by reduced oxygen consumption (VO2) and an increased respiratory exchange ratio (referred to as RQ in this instance), and basal insulin levels are increased in obesity (Smart et al., 2006). Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.