SNCA and multiple system atrophy: 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).