CRISPR/Cas9 genome editing is quickly revolutionizing biomedical research, but the new technology is not yet exact. The technique can inadvertently make excessive or unwanted changes in the genome and create off-target mutations, limiting safety and efficacy in therapeutic applications.
Now, researchers at UMass Medical School and the University of Toronto have discovered the first known “off-switches” for CRISPR/Cas9 activity, providing much greater control over the edits
Despite the power of the CRISPR/Cas9 system, it isn’t exact. There are times when the RNA guide used to maneuver the cleaving enzyme into the right position within the genome also targets the enzyme to other sequences that are similar but not identical. These mismatched sites, can sometimes also be cleaved, causing unintended damage.
This new study not only identifies that “off-switch,” but it shows that Cas9 inhibitors exist naturally and can be identified and exploited.
