METHOD OF PARALLEL, RAPID AND SENSITIVE DETECTION OF DNA DOUBLE STRAND BREAKS

The present invention relates to the field of gene editing and methods for its optimization and control. In particular, the present invention provides a method for detecting one or more double-strand breaks (DSBs) in DNA. The method of the invention is designated BreakTag and relies on directly labelling DSB ends. It is preferably used for discovering on- and/or off-targets of genome-editing nucleases, in particular CRISPR nucleases such as Cas9, Cas12 and variants thereof in vitro, in cells or in living organisms. In a core step, it uses a PCR suppression step to enrich for DSBs via tagmentation. The invention further provides a method for determining whether a CRISPR nuclease coupled with a specific gRNA generates a DNA DSB having blunted or a staggered ends. Finally, the invention provides kits and computer program products suitable for performing said methods.