It is important to note that the role of plasma insulin on muscle protein metabolism (Abdulla et al., 2016) and the associated insulin resistance in obesity, the effects of fasting on muscle protein metabolism (Bak et al., 2016), and whether protein metabolism is assessed under a fasting or fed state, as well as the interactions between feeding and physical activity on muscle protein metabolism (Miller, 2007), are all important factors that need to be considered when interpreting data from studies investigating the regulation of muscle protein metabolism in obesity. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.