While the buildup of misfolded α-synuclein and ubiquitin protein aggregates in LBs is associated with PD symptoms and death of dopaminergic (DA) neurons in the substantia nigra (Spillantini et al., 1997), the mechanistic basis of α-synuclein buildup and its toxicity leading to DA neuron death remains to be fully elucidated. Here, SNCA is linked to Parkinson disease.