For example, Fig. 6A shows that risperidone is predicted to be useful for the treatment of HD by decreasing the activity of the genes associated with the 5-hydroxytryptamine receptor (e.g., HTR1A, HTR2A, HTR2C, HTR7) and dopamine receptor (e.g., DRD2), which have been proven to be involved in the pathogenesis of depressive disorders [76, 77]. Here, HTR2A is linked to depressive disorder.