Traditionally, neurodegeneration has been framed as a brain-centric phenomenon, with pathology defined by hallmark protein aggregates: amyloid-β and tau in Alzheimer’s disease (AD), α-synuclein (α-syn) in Parkinsonian spectrum disorders (PSDs), TDP-43 in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) [5]. Here, SNCA is linked to Alzheimer disease.