NPAS2 and psychiatric disorder: Given the extensive disruption of circadian rhythms in SCZ and the strong genetic component involved in this psychiatric disorder, it is not surprising that several polymorphisms located at circadian-related genes such as retinoic acid-related orphan receptor (RORβ), Per2, Per3, and neuronal Pas domain protein 2 (NPAS2) have shown putative associations that confer a sizeable risk for SCZ [81].