A new tool to insert, delete and invert genes in a precise fashion could allow more sophisticated animal models of human diseases to be produced.
Francis Stewart at the Technical University of Dresden in Germany and his colleagues validated the potential of a previously discovered enzyme called Dre recombinase that cuts and rearranges DNA at specific target sites called rox. They show that it can be used to create mice in which specific gene sequences are disrupted.
The Dre-rox system does not cross-react with a commonly used system for genetically engineering mice called Cre-loxP, the authors found. Thus, the two systems could be used in combination to create knock-out mice with independent controls for multiple genes.