Heme oxygenase-1 (HO-1) is a stress response enzyme which in rodents and humans degrades heme to carbon monoxide, iron, and the potent antioxidant and anti-inflammatory molecule biliverdin, which is subsequently degraded to bilirubin [18, 19], thereby offering increased protection against obesity-induced ROS and hypertension [20]. The gene discussed is HMOX1; the disease is obesity due to melanocortin 4 receptor deficiency.