SNCA and multiple system atrophy: Examples of specific disease-associated proteins include alpha-synuclein (α-syn) in synucleinopathies such as PD and multiple system atrophy (MSA), amyloid-beta (Aβ) and tau in AD, polyglutamine-expanded huntingtin in HD, TAR-DNA-binding protein of 43 kDa (TDP-43) in ALS/FTD, as well as TDP-43, Cu/Zn superoxide dismutase (SOD), or fused in sarcoma (FUS) in ALS [12,17,18,19].