Skin and platelet α-synuclein as peripheral biomarkers of Parkinson's disease

Parkinson's disease (PD) is a heterogeneous disease that can be difficult to diagnose, and for which we have no simple effective biomarker. In this study we have investigated whether peripheral α-synuclein might represent a useful biomarker given that it has a central role in the pathogenesis of PD. We found that full length and truncated α-synuclein is present in platelets, but the amount is very variable and does not correlate with disease presence or severity. Furthermore, we show that α-synuclein can be detected by immunoblotting in some, but not all, human skin biopsies, but again its level does not correlate with disease presence or severity. We conclude that skin or platelet α-synuclein would not be an appropriate diagnostic biomarker for PD.