Site-specific DNA excision via engineered zinc finger nucleases

Abstract

To prevent gene flow from transgenic plants, an issue that raises environmental and regulatory concerns, Moon et al.[1] have proposed the use of site-specific recombinases and zinc finger nucleases (ZFNs) for transgene excision from pollen. According to their suggestion, a transgenic construct is flanked with the recognition sites of a site-specific recombinase, and this transgenic cassette is excised upon pollen-specific expression of the recombinase. Likewise, ZFNs can be employed to delete transgenes by making two concurrent double-strand breaks (DSBs) at the 5’ and 3’ ends of the cassette.