Genetic modification of Anopheles stephensi for resistance to multiple Plasmodium falciparum strains does not influence susceptibility to o'nyong'nyong virus or insecticides, or Wolbachia-mediated resistance to the malaria parasite.

Andrew Pike,George Dimopoulos

doi:10.1371/journal.pone.0195720

Abstract

Mosquitoes that have been genetically engineered for resistance to human pathogens are a potential new tool for controlling vector-borne disease. However, genetic modification may have unintended off-target effects that could affect the mosquitoes’ utility for disease control. We measured the resistance of five genetically modified Plasmodium-suppressing Anopheles stephensi lines to o’nyong’nyong virus, four classes of insecticides, and diverse Plasmodium falciparum field isolates and characterized the interactions between our genetic modifications and infection with the bacterium Wolbachia. The genetic modifications did not alter the mosquitoes’ resistance to either o’nyong’nyong virus or insecticides, and the mosquitoes were equally resistant to all tested P. falciparum strains, regardless of Wolbachia infection status. These results indicate that mosquitoes can be genetically modified for resistance to malaria parasite infection and remain compatible with other vector-control measures without becoming better vectors for other pathogens.

Highlights

Malaria is a disease of global public health concern that produces millions of cases each year and leads to hundreds of thousands of deaths, largely among children in sub-Saharan Africa [1]
The Plasmodium spp. parasites that cause malaria are vectored by various mosquitoes in the genus Anopheles, and control of these vector mosquitoes has been employed as part of many malaria control programs
Novel vector control methods are constantly being investigated, such the release of transgenic mosquitoes with reduced vector competence or breeding capacity and the use of the endosymbiotic bacterium Wolbachia to reduce the ability of the mosquitoes to spread disease [2, 3]

Summary

Introduction

Malaria is a disease of global public health concern that produces millions of cases each year and leads to hundreds of thousands of deaths, largely among children in sub-Saharan Africa [1]. The Plasmodium spp. parasites that cause malaria are vectored by various mosquitoes in the genus Anopheles, and control of these vector mosquitoes has been employed as part of many malaria control programs. Novel vector control methods are constantly being investigated, such the release of transgenic mosquitoes with reduced vector competence or breeding capacity and the use of the endosymbiotic bacterium Wolbachia to reduce the ability of the mosquitoes to spread disease [2, 3]. Despite the creation of numerous transgenic mosquito lines with reduced vector competence in various laboratories, there has been no release of such mosquitoes as part of a coordinated malaria control program, in part because of our lack of knowledge about the interactions of the genetic modifications with other mosquito control technologies

Methods

Results

Conclusion