Fig. 1

CSF α-Syn, Aβ42, t-tau, and p-tau₁₈₁ levels are lower in Parkinson’s disease than in controls. Box plot of the normalized CSF levels of a α-Syn. b total tau. c phosphorylated tau and d Aβ42 in controls (gray) and Parkinson’s disease cases (orange). Parkinson’s disease cases (N = 700) and controls (N = 189) from two independent datasets (WUSTL and PPMI). The means for each group are represented by a horizontal line. A generalized linear model (CSF biomarker levels ~ Age + Sex + Status) was used to calculate the statistical differences between the CSF protein levels in Parkinson’s disease cases and controls