58.5% iRBD patients showed baseline DAT deficit25 (28.7%) subjects developed clinically defined synucleinopathy (11 PD, 13 LBD, 1 MSA) during the follow-up period, with a mean latency of 3.2 ± 1.9 years from imaging.Subjects with abnormal baseline DAT-SPECT showed an increased risk of incident synucleinopathy during the follow-up period (reduced uptake greater than 25% in putamen discriminate patients at this risk). Here, SLC6A3 is linked to Parkinson disease.