DISC1 and schizophrenia: Of these dysregulated putative schizophrenia genes, changed expressions of DRD2, encoding the dopamine D2 receptor, a target of all antipsychotics in clinical use, and PDE4B, encoding a cAMP-degrading phosphodiesterase and known DISC1 interactor25, were confirmed by quantitative RT-PCR (Fig. 2e).