COSMOS MAGAZINE

Toxic semen to reduce disease-carrying mosquitoes

Words by Imma Perfetto

Researchers have developed a new pest control method known as the Toxic Male Technique (TMT), which works by genetically engineering male insects to produce venom proteins in their semen.

Males transfer the insecticidal proteins when they mate with females, significantly reducing the females’ lifespans.

Only the females of these species are capable of biting and transmitting disease, but TMT could make it possible to immediately suppress this population.

Insect-borne diseases pose a significant threat to human health, causing more than 700,000 deaths each year. This burden is expected to worsen as the warming climate alters the animals’ abundance and distribution.

Credit: Riccardo Niels Mayer

An overreliance on insecticides has led to the widespread emergence of resistance, so genetic biocontrol approaches are being used as an alternative to reduce populations of disease-spreading species.

Credit: SKT Studio

Current techniques, including the Sterile Insect Technique (SIT) or insects carrying lethal genes, work by releasing massive numbers of sterilised or genetically modified males to mate with wild females.

These females go on to produce no offspring or only male offspring. However, they continue to spread disease until they die naturally, so populations of biting females only decrease in the next generation.

A computer model to simulate the use of TMT in an Aedes aeqypti release program, found that TMT may reduce female blood feeding rates by 40–60% compared to leading biocontrol technologies.

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