CRISPR is mutating totally unrelated genes, and that’s a big problem

17 Jul 2018

Image: Yurchanka Siarhei/Shutterstock

CRISPR is once again under the spotlight as it struggles to show it can bring game-changing benefits to genetics without causing irreparable damage.

The gene-editing tool CRISPR continues to promise enormous changes in genetics and medicine, potentially enabling horrific conditions such as Huntington’s disease to be eradicated forever.

Since it first entered mainstream conversation, scientists have been working to see just what potential side effects could occur when a segment of DNA in cells is removed and replaced with another.

Now, the latest study published to Nature Biotechnology by a team from the Wellcome Trust Sanger Institute has shown that CRISPR causes greater genetic damage than was previously thought, potentially leading to highly dangerous, irreparable changes in some cells.

While this is not the first study to suggest there might be a problem with the tool, previous studies had not shown as many unforeseen mutations as seen during this latest testing in both mouse and human cells.

CRISPR changes could lead to important genes being switched on or off, the team found, which could have major implications for its use in therapies.

In addition, some of these changes were too far away from the target site to be seen with standard genotyping methods.

CRISPR companies get nervous

“This is the first systematic assessment of unexpected events resulting from CRISPR editing in therapeutically relevant cells, and we found that changes in the DNA have been seriously underestimated before now,” said Prof Allan Bradley, corresponding author of the study.

“It is important that anyone thinking of using this technology for gene therapy proceeds with caution, and looks very carefully to check for possible harmful effects.”

The discovery could drastically shake CRISPR research to its core, with researchers potentially turning to alternatives to the standard CRISPR method for gene editing.

Meanwhile, a number of companies working with CRISPR have downplayed the team’s findings. One such firm, Editas, said it was “an interesting topic” but had not shown up in its area of CRISPR-based medicines.

According to Fast Company, however, the news has not gone down well with shareholders in these firms, with a noticeable drop by as much as 6pc seen in shares.

Colm Gorey was a senior journalist with Silicon Republic