SLC6A3 and Parkinson disease: Demographics, baseline clinical characteristics and mean striatal specific binding ratios (SBR) computed from the dopamine transporter (DaT) SPECT imaging data (DaTscan) for PD manifesting and NMC of LRRK2 G2019S+ and R1441G+ were compared to sPD and HC groups (Table 1a, b, respectively).