Introduction: The aim of this study was to determine the mRNA expression profile of dopamine D1, D2, D3, D4 and serotonin 5-HT1A, 5-HT2A, and 5-HT3A receptors in peripheral blood mononuclear cells (PBMCs) in schizophrenia and the in vitro effect of antipsychotics on the expression of these receptors in PBMCs of healthy subjects. The gene discussed is HTR1A; the disease is schizophrenia.