The Parkinson's disease (PD) model mouse (tgPD mouse) created by the applicant mimics the pathogenesis of early-stage PD patients. Analysis of this tgPD mouse suggests that type I interferon (IFN-I) signaling may be involved in its pathogenesis. Furthermore, epidemiological data from hepatitis C patients suggest that IFN-I treatment may reduce PD risk. In this study, we will employ the tgPD mouse and human samples (postmortem brain and blood) to investigate the role of IFN-I in PD pathogenesis through sc-RNA-seq analysis and other approaches.