Several lines of evidence suggest that circadian misalignment and circadian clock gene disruption in humans and animals impact the comorbidities of metabolic disorders and cardiovascular risks such as obesity, diabetes, and atherosclerosis (Scheer et al., 2009; Paschos and Fitzgerald, 2010; Huang et al., 2011). Here, CLOCK is linked to obesity due to melanocortin 4 receptor deficiency.