SLC6A3 and major depressive disorder: Considering the common psychopathological aspects shared by anhedonia and hopelessness, such as the loss of motivation and negative beliefs, which seem to involve the dopaminergic reward system, the main aim of this study was to assess whether hopelessness is related to a peculiar striatal dopaminergic dysfunction in a sample of depressed patients; in addition, we assess suicidality through the use of a single item of Hamilton Depression Rating Scale, in order to evaluate a possible correlation between suicide risk and DAT availability.