Figure 1

Discrepancy in peak count and variable peak overlap between cell types. A) Number of ChIP-seq peak regions per TF in cell types K562 and HeLa-S3. The number of peaks varied for each TF, but there were also big differences between cell types for the same TF. B) Percentage of peaks found in promoter regions per TF in K562 and HeLa-S3. A promoter region was defined as the region 2000bp upstream and 200bp downstream of the RefSeq genes’ transcription start sites plus their first intron. On average, a third of all peaks were found in promoter regions. C) Peak overlap between K562 and HeLa-S3 relative to potential overlap; that is, the number of peak regions in K562 that overlap by at least one base pair with a peak region in HeLa-S3, divided by the lesser of the peak counts in K562 and HeLa-S3. 33% of K562 and 30% of HeLa-S3 peaks had at least one overlapping peak of the same TF in the other cell type.