Gene drive mosquitoes

In plain language

Malaria is spread by female Anopheles mosquitoes, which need blood to produce eggs. A gene drive is a genetic system that copies itself onto the matching chromosome, so far more of the offspring inherit the change than ordinary inheritance would allow. Researchers aim to use this to spread a trait that stops females from producing offspring, so that the mosquito population falls over several generations.

In laboratory cages, a gene drive built with CRISPR gene editing reached 100% prevalence in a major African malaria mosquito and caused the population to collapse within 7 to 11 generations. Those results come from closed cages. Wild mosquitoes move, feed and compete in complex ecosystems, and the researchers say that testing gene drive mosquitoes in the wild is still at least five to ten years away.

Technical explanation

The 2018 study by Kyrou, Hammond, Galizi and colleagues used CRISPR-Cas9 to target the doublesex gene in Anopheles gambiae. A drive construct aimed at this sequence spread rapidly in caged populations, reaching 100% prevalence within 7 to 11 generations and causing population collapse (Kyrou and colleagues, 2018).

Resistance is a main technical risk. Resistant alleles at the target site did not block the drive in the caged study. Whether this holds in wild populations, and whether drives can be contained or reversed if they spread beyond their target area, are open questions.

Field work has moved more slowly. Target Malaria, a project with partners in several African countries, reports a small-scale release of non-gene-drive genetically modified male-biased mosquitoes in Burkina Faso on 11 August 2025, carried out under national biosafety and environmental permits (Target Malaria, 2025). Authorities asked the project to suspend activities a week later, and the ministry announced the end of the project on 22 August 2025. The WHO Guidance Framework for Testing Genetically Modified Mosquitoes, second edition (2021), sets standards for developing, testing and regulating genetically modified mosquitoes. Its published description does not name gene drive.

What the evidence says

Each statement is typed by the strength of its evidence and linked to the source that supports it.

Limitations and open problems

• The gene drive results come from laboratory cages, not from the wild. The lead researcher said in 2018 that at least five to ten years would pass before gene drive mosquitoes were tested in the wild.
• Resistant alleles at the target site did not block the drive in the caged study. Whether this holds in wild populations is not known.
• Ecological effects in the wild are not yet known. The Imperial team says larger, more realistic trials are needed, since competition for food and other ecological factors could change how a drive behaves.
• Approval can be withdrawn: the Burkina Faso project was halted by the government in August 2025, after its non-gene-drive release.
• The WHO testing framework is guidance and does not by itself decide whether any gene drive release is approved.

Possible future uses

Timeline

1. 24 Sept 2018Imperial College London announces that a CRISPR-Cas9 gene drive collapsed caged Anopheles gambiae populations within 7 to 11 generations, with Professor Andrea Crisanti saying wild testing is at least 5 to 10 years away. Sources: [2], [1]
2. Dec 2018Kyrou, Hammond, Galizi and colleagues' paper 'A CRISPR-Cas9 gene drive targeting doublesex causes complete population suppression in caged Anopheles gambiae mosquitoes' appears in Nature Biotechnology volume 36, issue 11 (first published online 24 September 2018). Sources: [1]
3. 19 May 2021WHO publishes the second edition of the Guidance framework for testing of genetically modified mosquitoes. Sources: [3]
4. 11 Aug 2025Target Malaria reports a small-scale release of non-gene-drive genetically modified male-biased mosquitoes in Burkina Faso. Sources: [4]
5. 22 Aug 2025Burkina Faso's Ministry of Higher Education, Research and Innovation announces that it has terminated all Target Malaria activities in the country. Sources: [4]

Futures this could help bring about

How far away?

Fighting malaria with gene drive mosquitoes

Science demonstrated · 5 of 10 steps done

Related breakthroughs

• Multi-site gene drive suppressed caged malaria mosquitoes despite resistance alleles (6 Jul 2026)

Glossary

Gene drive

A genetic system that increases the chance that a gene is passed to offspring, so it can spread through a population faster than ordinary inheritance allows.

Population suppression

Reducing the size of a population, here a mosquito population, rather than replacing it with a modified one.

Anopheles gambiae

A mosquito species that is a major carrier of malaria in sub-Saharan Africa.

Resistant allele

A genetic variant that the gene drive cannot copy, which can stop the drive from spreading.

Sources

1. peer reviewed paper
   A CRISPR-Cas9 gene drive targeting doublesex causes complete population suppression in caged Anopheles gambiae mosquitoes
   K. Kyrou, A. M. Hammond, R. Galizi et al.. Nature Biotechnology, 24 Sept 2018. DOI: 10.1038/nbt.4245. Accessed 21 Oct 2026.
2. university press release
   Mosquitoes that can carry malaria eliminated in lab experiments
   Hayley Dunning. Imperial College London, 24 Sept 2018. Accessed 21 Oct 2026.
3. other
   Guidance framework for testing of genetically modified mosquitoes, second edition
   World Health Organization, 19 May 2021. Accessed 21 Oct 2026.
4. other
   Target Malaria activities suspended in Burkina Faso
   Target Malaria, 22 Aug 2025. Accessed 21 Oct 2026.

Revision history

3 changes since this profile was created.