Despite the rapid evolution of CRISPR-Cas systems, base editors, and prime editors, the tools used to characterise off-target activity have not always kept pace. Many widely adopted methods rely on indirect readouts, PCR-amplified libraries, or fragmented multi-assay workflows. Others measure the final genomic outcome long after editing has occurred, rather than capturing the break event itself. 

As editing programs move from early discovery toward IND-enabling studies, the pressure shifts from identifying events to discriminating between them. The challenge is no longer technical detection. It’s decision clarity.