SNCA and Parkinson disease: Parkinson’s disease (PD) is a common late-onset progressive neurodegenerative disorder characterized by loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) and the presence of fibrillar cytoplasmic inclusions composed of alpha-synuclein (αS) called Lewy Bodies (Thomas and Beal, 2007), as well as iron deposition (Altshuler and Hyde, 1985).