Gene drive systems that propagate transgenes via super-Mendelian inheritance can potentially control insect-borne diseases and agricultural pests. However, concerns have been raised regarding unforeseen ecological consequences, and methods that prevent undesirable gene drive effects have been proposed. Here, we report a chemical-induced control of gene drive. We prepared a CRISPR-based gene drive system that can be removed by a site-specific recombinase, Rippase, the expression of which is induced by the chemical RU486 in fruit flies. Exposure of fruit flies to RU486 resulted in 7-12% removal of gene drive elements at each generation, leading to a significant reduction in gene drive-fly propagation. Mathematical modeling and simulation suggest that our system offers several advantages over a previously reported gene drive control system. Our chemical control system can provide a proof-of-principle for the reversible control of gene drive effects depending on ecological status and human needs.
Keywords: CRISPR-Cas9 system; Rippase; gene drive; mutagenic chain reaction; population genetics.