Prime editing – an update on the field

At Gene Therapy , we are continually monitoring the landscape of research, noting those technologies which advance the goal of clinical translation of the field. In one of the most exciting ‘needle-shifting’ gene editing publications published in 2019, David Liu et al., (who pioneered base editing; BE [ 1 ]), developed ‘Prime editing (PE) [ 2 ]’, erasing several limits of CRISPR that have caused bottlenecks in its therapeutic and biotechnological applicability. Traditional gene editing strategies directing specific changes to the genome sequence itself largely reply on a common step – creating a double-strand break (DSB) to attract and exploit the DNA repair pathway machinery in executing the desired repair. This necessary ‘injury’ to the cell concomitantly contributes to many of the concerns in shifting gene editing to the clinic. This is where BE, and now PE, present technological inflection points on the road to advancing patient treatment. Put another way, say goodbye to DSBs and hello nicks. Thus, with the increased precision potential of PE, we can now accelerate clinical gene editing even further.