Two years of laboratory studies on the non gene drive genetically modified sterile male mosquitoes concluded successfully in Mali

Posted 9th November 2021 by Dr. Mamadou Coulibaly

The Target Malaria Mali team at the Malaria Research and Training Centre (MRTC) based at the University of Sciences, Techniques and Technologies of Bamako (USTTB) is proud to have been the first Malian research team to work on non gene drive genetically modified sterile male mosquitoes. The team has just published the results of the two years we spent studying these mosquitoes in our laboratory.

Thanks to this research, we have gained new knowledge and developed cutting-edge skills in the areas of entomology, molecular biology and genetics, allowing us to sustain a colony containing both local and genetically modified mosquitoes.

This research was made possible thanks to an authorisation from the Malian Ministry of Environment, Sanitation and Sustainable Development (MEADD) issued on 21 June 2019 to import a strain of non gene drive genetically modified sterile male mosquitoes and study them in a contained environment.

Initially designed at Imperial College London1, the genetically modified mosquitoes were then tested at Polo d’Innovazione di Genomica, Genetica e Biologia (PoloGGB) in Terni, Italy, before being transported to Mali. The mosquito eggs arrived by plane on 4 September 2019. They were kept in the insectarium renovated by the Target Malaria project.

Designed in compliance with the standards for Arthropod Containment Level 2 (ACL-2) making it suitable for handling genetically modified organisms, the insectarium is based at Point G on the campus of the University of Bamako. Over a period of two years, the scientists at the MRTC carried out experiments in the insectarium and the laboratory on the behaviour of genetically modified mosquitoes.

The sterile male mosquitoes were modified so that they cannot fertilise eggs. When sterile male mosquitoes reproduce, the eggs produced by the females do not hatch. The sterile males do not carry the gene drive technology. As a result, these mosquitoes do not remain in the environment because they do not produce any offspring and, like local mosquitoes, they die naturally after several weeks.

The goals of the study included developing the team’s skills, proving that the gene responsible for sterility could be passed on, demonstrating that the male mosquitoes are sterile, sustaining a colony of the new strain of sterile male mosquitoes and evaluating the behaviour of the genetically modified strain compared to local mosquitoes.

The team successfully achieved all of these objectives. The results were in line with the expectations of previous studies and confirmed that the introgression of the transgene into the local gene pool does not have any unexpected effects, thus supporting the conclusions set out in the risk assessments and confirming the safety of the system.

All planned experiments were completed successfully, enabling the team to develop their understanding and skills regarding the behaviour of the sterile male mosquitoes.

The Target Malaria Mali team is pleased to have successfully completed these two years of laboratory research in line with the authorisation conditions on a strain of genetically modified mosquitoes. It has submitted a final report to the National Biosecurity Committee and has shared its results with the regulatory authorities and other stakeholders.

For more information:
Results of laboratory studies on non gene drive genetically modified sterile male mosquitoes in Mali

1 The laboratory of Professor Andrea Crisanti, Imperial College London, UK