PELI1 and Parkinson disease: Since we previously demonstrated that Peli1 plays important roles in regulating the function of both CNS-resident microglia and peripheral immune cells19,20,22, so in order to examine the biological function of PELI1 during PD pathogenesis, we initially searched the public NCBI GEO database (GDS2519, GDS2821, GDS3128, GDS3129 and GDS4145) and examined the relative expression of PELI1 in SN, medullary regions, and peripheral blood mononuclear cells (PBMCs) that isolated from health donors (HD) and PD patients.