SNCA and Parkinson disease: Our findings here provide evidence that L-DOPA has an effect not only as a remedy for Parkinson’s disease palliation, but also as a disease-modifying drug by inhibiting α-synuclein aggregation and transmission, and further offer a compelling molecular rationale for the fact that administration of L-DOPA maintains motor functions for a long period, leading to improvement of QOL and prolongation of the survival time of PD patients.