BTC and schizophrenia: Selected serum analytes (among the 34 analytes betacellulin, bone morphogenic protein 6, eotaxin 3, follicle stimulating hormone and epidermal growth factor were significantly altered in first-onset antipsychotic naïve patients with schizophrenia compared to control subjects), were suggested to indicate a reproducible biological signature, but these studies need replication in larger population and in longitudinal studies [389].