In addition to DA neuron loss, the presence of intracellular inclusions called Lewy bodies (LBs) with an accumulation of protein aggregates including α-synuclein (α-SYN), and abnormal dystrophic neurites termed Lewy neurites (LNs) in surviving DA neurons, are also the major hallmarks of PD pathology (Kalia and Lang, 2015). The gene discussed is SNCA; the disease is Parkinson disease.