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.
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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