SNCA and Alzheimer disease: In neurons, autophagy is vital due to their post-mitotic nature and polarized long processes; deficits in autophagy contribute to aggregate accumulation in AD (accumulation of autophagic vacuoles with Aβ), PD (impaired clearance of α-synuclein), and ALS (aggregates of SOD1 or TDP-43) [35,36].