A confinable home-and-rescue gene drive for population modification

Area of Science:

• Genetics
• Molecular Biology
• Population Genetics

Background:

• CRISPR/Cas9 gene drives offer potential for population modification.
• Resistance alleles can impede the spread and efficacy of gene drives.
• A confinable gene drive system is needed to mitigate risks and enhance control.

Purpose of the Study:

• To engineer and evaluate a home-and-rescue (HomeR) gene drive for confinable population modification in Drosophila.
• To assess the impact of resistant alleles and fitness costs on HomeR drive efficacy.
• To compare HomeR with other gene drive architectures through mathematical modeling.

Main Methods:

• Engineered a home-and-rescue (HomeR) gene drive targeting an essential gene in Drosophila melanogaster.
• Conducted population cage experiments to measure drive frequency and efficacy.
• Performed mathematical modeling to compare HomeR performance against other gene drive systems under various conditions.

Main Results:

• HomeR drive demonstrated an increase in frequency in population cage experiments.
• Recessive lethal resistant alleles were disadvantageous, limiting their accumulation.
• Fitness costs associated with the Cas9 insertion reduced overall drive efficacy.
• Mathematical modeling provided insights into HomeR's performance relative to other drive systems.

Conclusions:

• The HomeR drive system shows promise for controlled population modification in Drosophila.
• Fitness costs associated with Cas9 insertion are a key factor influencing drive efficacy.
• HomeR offers a potentially safer and more adaptable alternative for future gene drive applications in other species.