What is the risk of getting a disease from a genetically modified mozzie?
Mosquitoes are responsible for spreading many diseases, such as malaria, What is the risk of getting a disease from a genetically modified mozzie?
Mosquitoes are responsible for spreading many diseases, such as malaria, lymphatic filariasis (also known as elephantiasis), and the o’nyong’nyong virus first found in Uganda, and since seen in other countries, such as Nigeria, Kenya and Tanzania.
One method of preventing these mosquito-borne diseases is to use insecticides to kill the mozzies and remove them, but sometimes this only works as a short term solution, or has unintended effects on the ecosystem.
Another method for decreasing the number of disease-carrying mozzies is to introduce ways to suppress the population using genetically modified mozzies.
These transgenic mozzies could be part of a gene drive system where they have a newly introduced disease-resistant gene, linked up with mechanisms that help the gene dominate in the population by continuing to copy itself through the genome. Alternatively, the gene drive could help decrease the number of mosquitoes altogether, without the need for pesticides.
All of this requires very thorough risk assessment.
In a new study by CSIRO, led by Geoffrey Hosack, researchers have done a thorough risk assessment of transgenic mosquitoes by combining scientific theory, mathematical models and empirical data about whether disease would actually decrease.
The risk of getting malaria from the transgenic mosquitoes was lower for all three of the previously mentioned diseases, compared to wild mosquitoes, they show in their paper, published in Royal Society Open Science.
They predicted that releasing transgenic mozzies with a sterile male construct lowered the chance of getting a secondary infection from a mozzie bite by at least six times, and, in some cases by over 1000 times, depending on the disease. These transgenic mosquitoes could be part of a phased pathway for population suppression using gene drive.
“Scientific risk assessment for a release of transgenic vectors is an interdisciplinary exercise,” they say in their paper. It requires complex mathematics and an understanding of ecology and genetics, but this type of model could potentially be used for risk assessments of other transgenic insects and controlling disease, too.