The neuropathology of PD is principally defined by the loss of dopaminergic neurons in the midbrain substantia nigra (SN)-pars compacta, and immunoreactive deposits of α-synuclein (aSyn; gene symbol SNCA) protein across multiple regions in the central nervous system (CNS) [1, 2, 4]. This evidence concerns the gene SNCA and Parkinson disease.