Overview of the study. (A) Retina and brain microglia share a common origin from the yolk sac. (B,C) Integration of single-nucleus RNA sequencing (snRNA-seq) and single-nucleus ATAC sequencing (snATAC-seq) data from 97 human retina and brain microglia samples. (D) Integration of genome-wide association study (GWAS) data for age-related macular degeneration (AMD) and Alzheimer's disease (AD) with transcriptomic and epigenetic annotations using various enrichment methods.