SNCA and Parkinson disease: The pathological hallmarks of PD have been defined as dopamine (Dop) depletion resulting from the progressive loss of nigrostriatal dopaminergic neurons in the substantia nigra pars compacta (SNpc) and locus coeruleus (LC) and as the presence of cytoplasmic inclusions called Lewy bodies, mainly formed by fibrillar α-synuclein [86].