Figure 1. Model for How DNA Damage Occurs at Chromatin Loop Anchors.

After recruitment by the cohesin loader, cohesin slides along chromatin, extruding a chromatin loop and inducing torsional strain in the chromosome, until its movement is stopped by encountering CTCF. Topoisomerase TOP2B is recruited to the chromatin loop anchor to relieve the torsional strain by breaking and resealing the DNA, but occasionally it does not reseal the breaks, leading to oncogenic chromosome rearrangements.