SNCA and Parkinson disease: PD is clinically characterized by rigidity, resting tremors, and bradykinesia [2], pathologically characterized by the presence of Lewy bodies (LB); the main component is accumulated misfolded α-Synuclein (α-Syn) [3, 4] and progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNc) [5, 6].