UCP1 and obesity due to melanocortin 4 receptor deficiency: WAT is specialized as an energy reservoir to store excess chemical energy in the form of triglycerides that can be released as free fatty acids into the circulation in times of food shortage [5], while BAT is responsible for dissipating chemical energy as heat to protect against hypothermia and obesity-dependent uncoupling protein 1 (UCP-1)-induced thermogenesis [6,7].