Based on previous findings that the striatum and corticobasal ganglia pathways play an important role in the neuropathology of affective disorders and subsequent suicidal behaviors [91] and are associated with reward prediction involved in decision-making [92], one study suggested that the reduced availability of SERT in the striatum in patients with MDD and depression may contribute to the development of suicidal action [61]. Here, SLC6A4 is linked to major depressive disorder.