SLC6A3 and supranuclear palsy, progressive, 1: Dopamine deficiency observed on DAT scans can also be seen in Parkinson’s plus syndromes and could be indicative of multiple system atrophy (MSA), progressive supranuclear palsy (PSP), cortical-basal ganglionic degeneration (CBGD), and dementia with Lewy bodies (DLB).