These increases in whole blood expression are, in part, supported by previous studies that have shown an increased AKT1 mRNA expression in PBMCs from individuals with early-onset (23) and treatment-naïve schizophrenia (46), suggesting peripheral upregulation of NRG–ErbB pathway transcripts may not be specific to the stage of illness and may occur during the first phases of schizophrenia and continue during the chronic phases. This evidence concerns the gene EGFR and schizophrenia.