EVs are also involved in the cell-cell transport of pathogenic proteins associated with neurodegenerative diseases, such as the prion protein (PrP) abnormal isoform PrPSC in prion disease, β-amyloid in Alzheimer’s disease and α-synuclein in Parkinson’s disease [86,87]. The gene discussed is PRNP; the disease is early-onset autosomal dominant Alzheimer disease.