PER1 and obesity due to melanocortin 4 receptor deficiency: Obesity resulted in overall disruption of core clock genes (i.e., Bmal1, Clock, Rev-erbα/Nr1d1, Rev-erbβ/Nr1d2, Per1, Per2, Cry1, Cry2, Dbp and Rorα) in WAT (Figure 1B-C & Figure S2).