Lina Pan et al. demonstrated that tau proteins interact with α-Syn and accelerate its aggregation; that tau-modified α-Syn protofibrils have a stronger spreading activity than pure α-Syn protofibrils and induce mitochondrial dysfunction, synaptic dysfunction, and neurotoxicity; and that tau protein promotes the aggregation and spread of α-Syn in PD [48]. The gene discussed is MAPT; the disease is Parkinson disease.