ABSTRACT
CRISPR-based gene-drive systems have been proposed for managing insect populations, including disease-transmitting mosquitoes, due to their ability to bias their inheritance towards super-Mendelian rates (>50%). Current technologies employ a Cas9 that introduces DNA double-strand breaks into the opposing wildtype allele to replace it with a copy of the gene drive allele via DNA homology-directed repair. Yet, the use of different Cas9s versions is unexplored, and alternative approaches could increase the available toolkit for gene-drive designs. Here, we report a novel gene-drive approach that relies on Cas9 nickases that generate staggered paired nicks in DNA to propagate the engineered gene-drive cassette. We show that generating 5’ overhangs in the system yields efficient allelic conversion. The nickase gene-drive arrangement produces large, stereotyped deletions that are advantageous for targeting essential genes. Indeed, our nickase approach should expand the repertoire for gene-drive designs aimed at applications in mosquitoes and beyond.
Competing Interest Statement
V.M.G. has equity interests in Synbal, Inc. and Agragene, Inc., companies that may potentially benefit from the research results and also serves on both companies’ Scientific Advisory Board and on the Board of Directors of Synbal, Inc. The terms of this arrangement have been reviewed and approved by the University of California, San Diego in accordance with its conflict-of-interest policies. V.L.D.A, and S.S.J declare no competing interests.
