a–c, Snapshots of KAS-seq signals at selected small RNA, tRNA, and rRNA loci in HEK293T cells under native, DRB treatment, and triptolide treatment conditions. d, A summary of different types of non-B form DNA structures and the number of KAS-seq peaks (under triptolide-treatment condition) detected at each type of predicted non-B form DNA regions. e, Snapshots from UCSC genome browser showing examples of KAS-seq signals under native, DRB, and triptolide-treatment conditions at different non-B form DNA regions and telomeric DNA regions. f, Enrichment of KAS-seq signals at different non-B form DNA and telomeric DNA regions showed in (d). n = 715 regions for hairpin, n = 1,643 regions for cruciform, n = 730 regions for H-DNA, n = 356 regions for quadruplex, n = 256 regions for Z-DNA, n = 29 regions for telomere.