DHSs We used the DHS data from 80 experiments from ENCODE13 and 137 experiments from the NIH Roadmap Epigenomics Project14 (Table S2). We downloaded chromatin immunoprecipitation sequencing reads mapped to hg19 (UCSC Genome Browser) and merged reads from replicate samples. Using a corresponding input DNA library as the control if available, we ran MACS v.2.022 with default settings (false-discovery rate [FDR] = 0.01; bandwidth = 300 bp) to identify significant peaks. In total, analysis of 217 experiments yielded 1,331,772 distinct autosomal DHSs, collectively spanning 16.4% of the genome. We combined DHS tracks across all cell types into a single consolidated DHS track by identifying the genomic positions that overlap DHSs in any cell type.