One of the barriers to using CRISPR-Cas9 gene editing in the clinic is the possibility that the enzyme will clip DNA in the wrong spot. In a study published in Nature today (September 12), researchers describe a strategy to predict these off-target mutations throughout the genome and show in mice that a carefully designed guide RNA strand does not produce any detectable slip-ups.
The study confirms that “you’d better make sure that you’ve got a really accurate guide RNA,” says Janet Rossant, a developmental biologist at the University of Toronto and the Hospital for Sick Children who did not participate in the work. “This [method] is a better way of testing for how specific that guide RNA will be before you go into animal models and, of course, into humans,” she adds.
According to coauthor Marcello Maresca, a biologist at AstraZeneca in Sweden, one long-term goal of his ...