Assessing a natural gene drive for population control in house mice

Abstract

House mice are a major invasive pest with significant impact on island ecosystems. Genetic biocontrol via gene editing offers promising new avenues for population control. An alternative idea dating back over half a century is to harness the unmodified, naturally occurring genetic element called t haplotype for population suppression. The t haplotype causes sterility in t/t homozygote males, while +/t heterozygote males transmit the t to most of their offspring via meiotic drive. We use population genetic modelling to systematically explore whether this approach can suppress invasive populations through the accumulation of t/t sterile males. We find that +/t fertile releases combined with the sustained release of t/t sterile males can achieve eradication, but require prolonged interventions, with eradication taking around 25 years under our baseline scenario. We then show that release effort and eradication times may be reduced substantially if releases are combined with trapping, culling, or the release of hyper-competitive (Adonis) males. A direct comparison with tCRISPR, currently the main engineered genetic biocontrol system for house mice, shows that the approach requires greater release effort but achieves comparable eradication times. We provide an R shiny application for exploring model scenarios interactively. Our findings highlight both the potential and the limitations of exploiting this natural meiotic drive system for population control, and identify key gaps in knowledge of mouse reproductive biology and behaviour needed to fully assess its feasibility in the field.