Developing Aedes albopictus population control with precision guided sterile males

The global spread of the Asian tiger mosquito, Aedes albopictus poses a widening epidemiological threat. Its rapid expansion and vectorial capacity for various arboviruses is therefore affecting an increasingly larger proportion of the world population. In many areas, including Israel, this mosquito is established and thriving. Genetic control strategies (GCSs) are environmentally-friendly alternatives to traditional approaches for suppressing mosquito populations. Among GCSs, the sterile insect technique (SIT) relies on large-scale release of sterile insects which has challenges with large-scale sex-separation and male viabillity. pgSIT is a system, which incorporates modern CRISPR/Cas9 genome-editing to precisely induce both full male sterility and sex-separation within a framework. Development of precision guided SIT systems in the Asian tiger mosquito will make a contribution towards the application of a novel, area-wide mosquito genetic control strategy. Establishment of pgSIT requires a set of genetic engineering tools that Aedes albopictus is lacking. The components required for establishing this system consists of developing two separate transgenic insect strains, each expressing one of the two components of the CRISPR/Cas9 system - either the Cas9 DNA endonuclease or the sgRNA that guide the Cas9 endonuclease to precise genomic target sequence. To address this need, here we systematically engineer pgSIT in Aedes albopictus using a system that disrupts genes essential for male fertility and female vitality, which is essential for mating, blood feeding, reproduction, and predator avoidance—meaning survival in general.