Parkinson’s disease (PD) is primarily characterized by progressive accumulation of aggregated α-synuclein in the brainstem, leading to a degeneration of dopaminergic neurons in substantia nigra (Lang and Lozano, 1998; Xu et al., 2002; Braak et al., 2003; Kraemmer et al., 2014). Here, SNCA is linked to Parkinson disease.