Parallel and multistep analysis in this research showed that SLC1A1, DRD2, DRD4, BDNF, ESR1, CDH2, GRIN2B, TNFa, GABBR1, and OLIG2 are common genes between schizophrenia and OCD which ESR1, DRD2, GABBR1, TNFa, and CDH2 are the most important individuals. The gene discussed is DRD4; the disease is schizophrenia.