When people talk about the gene-editing technology CRISPR, it’s usually accompanied by adjectives like “revolutionary” or “world-changing.” For this reason, it’s no surprise that a study out last month questioning just how game-changing the technology really is caused quite a stir.
It’s well-known that using CRISPR can sometimes also result in some unintended genomic changes, and scientists have long been working on ways to fine-tune it. But the researchers found that when they had used CRISPR to cure blindness in mice, it had resulted in not just a few but more than a thousand, unintended off-target effects.
“This finding warns that CRISPR technology must be further tailored, particularly before it is used for human gene therapy,” the researchers wrote. The technique has already been used in two human trials in China, and next year one is slated to kick off in the US.
Their finding kicked off a battle for CRISPR’s honor, with some researchers speaking out to question the study’s methods while others piped up to agree that CRISPR is not yet ready for people.