(A) Performing ATAC-seq in a pool of individuals selects DNA molecules with higher CA, thus enriching for more accessible alleles. In this example (ASW population), the G allele has a low pre-ATAC frequency but a high post-ATAC frequency, due to its increased CA. The ten population abbreviations refer to: CEU, Utah residents with North European ancestry; FIN, Finnish; TSI, Tuscan; IBS, Iberian; ASW, African-American from Southwest US; YRI, Yoruban; ESN, Esan; LWK, Luhya; GWD, Gambian; and CHB, Han Chinese. (B) The number of caQTLs (top), and the percent of all tested SNPs called as caQTLs (bottom). (C) Enrichment of caQTLs among dsQTLs (Degner et al., 2012), at a range of caQTL p-value cutoffs. (D) Quantitative effect sizes of caQTLs and dsQTLs are highly correlated (scales of each axis are not comparable, and do not affect the correlation coefficient).( E–F) The degree of allelic concordance between our caQTLs and: (E) dsQTLs (Degner et al., 2012). (F) bQTLs aggregated for five TFs (Tehranchi et al., 2016). Full results available in Figure 1—source data 1.