In a recent study of 275 PD patients and 144 controls, as well as atypical PD cohorts, neuronal EVs were isolated using L1CAM immunocapture, followed by mass spectrometry or electrochemiluminescence to measure proteins including alpha-synuclein and clusterin106: Compared with controls and other neurodegenerative conditions including MSA, levels of mean neuron-derived exosomal alpha-synuclein were two-fold higher in clinical PD and prodromal PD, with an AUC of 0.86 for separating patients with PD from controls106. This evidence concerns the gene SNCA and Parkinson disease.