DRD2 and major depressive disorder: No statistically significant differences were found in the total mental health score and the scores of various factors among the DRD2 gene rs1799732 genotypes (P > 0.05), and no differences were observed in the total mental health score, somatization, obsessive symptoms, interpersonal sensitivity, depression, anxiety, hostility, fear, paranoia, and psychosis scores corresponding to the DRD2 gene rs1799732 genotypes.