It has been well-established that dopamine D2 receptor (D2R) antagonism with 5-HT receptor type 2A (5-HT2AR) antagonism or 5-HT1AR partial agonism, with well-known receptor binding profiles in atypical antipsychotics, contribute to the clinical efficacy of antipsychotics against positive and negative symptoms of schizophrenia (44, 45). This evidence concerns the gene DRD2 and schizophrenia.