SNCA and Alzheimer disease: Lewy body disease (LBD), the second most prevalent neurodegenerative disorder after Alzheimer's disease (AD), is characterized by the misfolding and aggregation of alpha-synuclein (αSyn), resulting in the formation of cytoplasmatic neuronal inclusion in cell bodies (i.e., Lewy bodies [LBs]) and nerve terminals (i.e., Lewy neurites [LNs]) [36, 61].