The histopathological features of PD include the loss of dopamine in nigrostriatal neurons as well as the presence of α-synuclein-positive, intracytoplasmic inclusions known as Lewy bodies both in the dopaminergic cells of the substantia nigra (SN) and in other regions of the central nervous system (Dickson 2012). The gene discussed is SNCA; the disease is Parkinson disease.