Off Target: Reporting on Human Embryo Gene Editing

Major news outlets recently reported – based on a bioRxiv preprint – that scientists had edited genes in human embryos with “startling precision.” The scientists’ decision to release this work ahead of peer review, coupled with the extensive media coverage, raises ethical concerns because it risks making disruptive gene-editing technology appear safer and more inevitable than the evidence supports. It also contributes to the normalization of a tool that may be used more for human enhancement than treatment of serious diseases.

Previous attempts to use CRISPR/Cas9 gene editing in human embryos frequently resulted in chromosomal abnormalities and off-target changes, posing major barriers to the safety and efficacy of heritable genome editing. In their preprint, Dieter Egli and colleagues reported on a gene editing approach called base editing that they used to modify disease risk. Their approach reduced chromosomal abnormalities, but off-target changes remained.

Scientists share preprints prior to peer review to accelerate scientific exchange. Posting on preprint servers was widely adopted for the rapid dissemination and communication of Covid-19 research. However, short-circuiting the peer-review process also has risks: The findings...