Although PDE10A inhibition has shown promise as a novel target of the treatment of schizophrenia,15 recently the first positron emission tomography (PET) study of PDE10A expression in patients with schizophrenia found no difference compared to healthy controls using the [11C]IMA107 ligand.16 However, the sample size was small and did not include treatment-resistant patients treated with diazepines such as clozapine. This evidence concerns the gene PDE10A and schizophrenia.