From the earliest days of the CRISPR-Cas9 era, scientists have known that the first step in how it edits genomes — snipping DNA — creates an unholy mess: Cellular repairmen frantically try to fix the cuts by throwing random chunks of DNA into the breach and deleting other random bits. Research published on [July 16] suggests that’s only the tip of a Titanic-sized iceberg: CRISPR-Cas9 can cause significantly greater genetic havoc than experts thought, the study concludes, perhaps enough to threaten the health of patients who would one day receive CRISPR-based therapy.
The results come hard on the heels of two studies that identified a related issue: Some CRISPR’d cells might be missing a key anti-cancer mechanism and therefore be able to initiate tumors.
The DNA chaos that CRISPR unleashes has been “seriously underestimated,” said geneticist Allan Bradley of England’s Wellcome Sanger Center, who led the study. “This should be a wake-up call.”
Read full, original post: Potential DNA damage from CRISPR has been ‘seriously underestimated,’ study finds