MC4R deficiency in rodents and humans (Fan et al., 2000, Farooqi et al., 2003) is characterized by low blood pressure (BP; for the degree of obesity) due to impaired sympathetic nervous system activation (Greenfield et al., 2009, Sayk et al., 2010, Simonds et al., 2014, Tallam et al., 2005). This evidence concerns the gene MC4R and obesity due to melanocortin 4 receptor deficiency.