While a strong correlation was also seen between PD and PSP, we identified 11 proteins (SLC35A4, FTH1, MICOS10, SAR1B, RAB2A, CDC42, RHOA, GNA13, RAB35, YKT6, VPS13C) upregulated in PSP but downregulated in PD (and in MSA). This evidence concerns the gene YKT6 and multiple system atrophy.