Evading evolution of resistance to gene drives
Evading evolution of resistance to gene drives
Tags: CRISPR, Gene drive synthetic, Population suppression, Replicator/site directed nuclease, ResistanceR. Gomulkiewicz, M. L. Thies and J. J. Bull, bioRxiv, 2020.
Gene drives offer the possibility of altering and even suppressing wild populations of countless plant and animal species, and CRISPR technology now provides the technical feasibility of engineering them. However, population-suppression gene drives are prone to select resistance, should it arise. Here we develop mathematical and computational models to identify conditions under which suppression drives will evade resistance, even if resistance is present initially. We show that linkage between the resistance and drive loci is critical to the evolution, that evolution of resistance requires (negative) linkage disequilibrium between the two loci. When the two loci are unlinked or only partially so, a suppression drive that causes limited inviability can evolve to fixation while causing only a minor increase in resistance frequency. Once fixed, the drive allele no longer selects resistance. Single drives of this type would achieve only partial population suppression, but multiple drives (perhaps delivered sequentially) would allow arbitrary levels of suppression. Given that it is now possible to engineer CRISPR-based gene drives capable of circumventing allelic resistance, this design may allow for the engineering of suppression gene drives that are effectively resistance-proof.Competing Interest StatementThe authors have declared no competing interest.
