Sex Sorting for Pest Control: It's Raining Men!

In the pursuit of better pest- and vector-control strategies, attention returns to an old proven technology, the sterile insect technique (SIT) and related insect population-suppression methods. A major obstacle for any of these approaches that involves the release of sterile males is the separation of males from females during the mass rearing stage, in order to improve the cost-efficiency of these methods and to prevent the release of biting and disease-vectoring females. This review describes recent sex-sorting developments in dipteran flies with an emphasis on assessing the suitability of these methods for large-scale rearing of male vectors for mass release. Sexing Diptera represents a major obstacle to operationalizing vector-control methods based on the mass release of males, such as the sterile insect technique or the incompatible insect technique. The recent progress made in gene editing, as well as the growing understanding of sex-determination pathways in Diptera, offer new perspectives to develop sexing systems in target species that allow female elimination during mass rearing. The developmental stage at which the sexes are separated, or females are eliminated, is one of the key parameters for assessing the cost efficiency of a sexing technology. Challenges remain in the development of sex-separating systems that are used early in mass rearing, without major genetic defects or lack of competitiveness in produced males, as well as good social and regulatory acceptability of the methods used, considering their operational deployment in the field. [ABSTRACT FROM AUTHOR]