CLOCK and obesity due to melanocortin 4 receptor deficiency: Twelve obesity-predisposing genetic variants were found to be associated with a MUHO [34], which regulates physiological processes, including food intake (LEP), circadian rhythm (CLOCK), signaling at the synapses (CNR2 and BDNF), secretion of bile (ABCB11), expenditure of energy (UCP3), metabolism of lipids (PLIN1 and PPARGC1A), production of hormones (GNAS), reward-personalization genes (ANKK1), and insulin signaling processing genes [114, 115].