GBA1 and Parkinson disease: Out of a total of 2428 genes mapped to PD-GWAS regions, defined as ± 500 Kb of GWAS-SNVs, 628 were DEGs in at least one cell subtype (hereafter designated as PD GWAS-DEGs), including SNCA (Exc5 and Micro3), GBA (Inh2), and LRRK2 (OPC1) (Fig. 2C, Fig. S4B, Table S3).