The accumulation of aggregated and fibrillar forms of α-synuclein (α-syn) in neurons is a defining hallmark of several neurodegenerative diseases that include Parkinson’s disease (PD), multiple system atrophy (MSA), and dementia with Lewy bodies (DLB), which are collectively referred to as synucleinopathies (1, 2). This evidence concerns the gene SNCA and Parkinson disease.