5.03 - Genetic sexing for Sterile Insect Technique programs

Genetic sexing is a critical component of the Sterile Insect Technique (SIT), enabling male-only releases that significantly enhance pest suppression while reducing ecological and operational costs. This chapter reviews the evolution of genetic sexing systems (GSS) from classical methods to advanced genome-editing strategies. It covers key technologies including temperature-sensitive lethal mutations, transgenic female-lethal constructs, fluorescent markers, and CRISPR-based approaches such as X-shredding and neoclassical edits targeting conserved loci like lysine--tRNA ligase. Applications across multiple insect pest species are discussed, alongside regulatory and scalability considerations. Despite their promise, current GSS face challenges in long-term genetic stability, field robustness, and public acceptance, particularly for transgenic approaches. Future directions emphasize the development of non-transgenic, high-fidelity systems, improved strain management under mass-rearing conditions, and integration of automated sorting technologies. Advancing GSS technologies will be essential for expanding SIT to a broader array of agricultural and vector species within sustainable pest control frameworks.