SNCA and Lewy body dementia: α-synucleinopathies are neurodegenerative disorders characterized by the presence of abnormal α-synuclein (α-syn) inclusions in the brain, predominantly in neurons in Parkinson’s disease (PD) and dementia with Lewy bodies (DLB), and in oligodendrocytes in multiple system atrophy (MSA) [1–5].