Considering that tau can induce α-synuclein aggregation [63] and that deposits of both proteins can be found in PSP [64], it is possible that time-mediated accumulation of tau aggregates would promote o-α-synuclein misfolding and deposition, progressively reducing the pool of free molecules of this protein in serum of PSP patients. This evidence concerns the gene MAPT and supranuclear palsy, progressive, 1.