A neurobiological factor (biomarker) that predicted a shorter survival in PD was reduced DAT uptake in the striatum, particularly in the caudate nucleus (1.48 times higher hazard for death for each SD of lower uptake), while the baseline CSF protein concentrations of neurodegenerative markers and APOE genotype were not predictive (table 4). This evidence concerns the gene SLC6A3 and Parkinson disease.