SNCA and Parkinson disease: Parkinson’s disease is characterized by the presence of Lewy bodies, mainly composed of alpha-synuclein fibrils, a depletion of dopamine (DA)-generating neurons in substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) regions of the brain (Wirths and Bayer, 2003; Dexter and Jenner, 2013), that results in a decrease of DA levels in the striatum and frontal cortex regions of the brain (Thompson et al., 2005).