WIKIMEDIA, RAMAThe work of researchers who use the CRISPR gene-editing technique to precisely clip genetic sequences from mouse chromosomes just got a little bit easier. Scientists at the Broad Institute of MIT and Harvard have unveiled the “Cas9 mouse,” a model organism that naturally expresses Cas9, the cleaving enzyme that cuts DNA in exact spots along the genome with the help of a guide RNA. Currently, using CRISPR means injecting both Cas9 and guide RNA into cells to edit a specific part of the genome. But with Cas9 mice, researchers will only have to inject the guide RNA, which pilots the Cas9 to the target gene sequence, in order to alter virtually any part of the mouse genome.
This will allow quicker and easier gene knock-down experiments, for example, because having on-board Cas9 makes more room in vectors used to deliver the guide RNA to contain multiple instructions for genome editing in the knock-in mice. “By equipping the mouse with Cas9, we relieved the burden of delivery,” MIT’s Randall Platt, a coauthor on the September 25 Cell paper announcing the creation of the Cas9 mouse, said in a statement. “This frees up space for the delivery of additional elements—whether by viruses or nanoparticles—making it possible to simultaneously mutate multiple genes and even make precise changes in DNA sequences.”
No longer will researchers seeking to mouse lines that model human cancers, for instance, have to inactivate one gene at a time or cross animals ...
