Fig. 6

Clustered CTCF sites overlap more frequently with cohesin and locate closer to genes, compared to singleton CTCF binding sites. a 93.7% of the clusters of CTCF binding sites demonstrate colocalization with the cohesin subunit RAD21, while the respective fraction of extended singleton CTCF sites is 69% (χ² test: p < 2.2e−16). The singleton CTCF binding regions were extended by a few kilobases prior to intersection with RAD21 binding regions to ensure the mean of their length distribution is equal to the mean length distribution of clusters of CTCF sites. b CTCF sites that belong to clusters (clustered) are located closer to gene TSSs (median distance = 5.3 kb) than singleton CTCF sites (median distance = 10.9 kb) (Mann-Whitney U test: p < 2.2e−16)