Malaria kills a staggering 650,000 plus people each year, and most of those are children. It’s a deadly disease spread by the tiny mosquito, and to date, most attempts of trying to eliminate the mosquito and reduce the casualties have failed. Malaria is prevalent in Africa and South America, and although it was eliminated some 60 years ago in the United States, approximately 1,500–2,000 cases are reported every year in the country, almost all in recent travelers. Perhaps though scientists are one step closer to finding a solution to a worldwide health problem by genetically engineering wild mosquitoes!
A recent study reported in eLife confirmed scientists had discovered the latest technology for altering DNA may stop the malaria parasite from spreading within mosquitoes by making the insect resistant to it. Go one step further, and it may be possible to engineer infertility into the DNA of mosquitoes which will, in turn, reduce their population eventually into oblivion.
So How Does it Work?
The system of altering the DNA is known as Crispr, and it allows scientists exquisite precision. A molecule is designed so that DNA can attach at specific locations. The DNA is sliced out, either in full or just part of the gene. This encourages a cell to replace the segment with a new component designed by scientists. To date, researchers have been able to alter the DNA of cells and animals in the lab.
With malaria, scientists would insert a bundle of genes into mosquitoes in the lab. Within this group of genes would be a protein that causes mosquitoes to become resistant to the malaria parasites while accommodating genes from the CRISPR molecules.
Once this procedure is complete, the mosquitoes would be released into the wild where they would continue their life cycle as per usual, mating with other wild mosquitoes. The offspring of these mosquitoes would now contain the altered DNA, and the CRISPR genes would go about producing their molecules within the mosquito’s cells, altering them from within.
These clever Crispr molecules would target a gene in the wild mosquitoes’ DNA passed down to the offspring, and in turn, they would replace this DNA with the resistance gene. This would mean the new mosquito would have two copies of the malaria-resistant gene instead of one. Incredible right?
How Long Would it Take for Mosquitoes to Become Resistant?
The Crispr molecule is designed to spread the resistance genes very quickly and accurately. The assumption is, within only a few years the whole population of mosquitoes could become resistant to the malaria parasite.
Crispy is also a product that can potentially work in almost any species of animal, plant or fungus. For example, it could be possible for a scientist to use the CRISPR molecules to alter the gene of invasive weeds and return them to their defenseless state.
Where to Now?
This latest development in the fight against malaria is at its very early stages. However, authors of the reports are wanting the process of altering the DNA of wild species to be publically discussed because while it may be a breakthrough in human health, it could lead to unforeseen ecological harm. Questions are being asked whether it is right to target an invasive species in a country with malaria issues, with the potential to pass on the genes to mosquitoes in another country who have an important role to play in the entire ecosystem.
On the other hand, there have been extraordinary breakthroughs where Crispr has been shown to fix a mutation causing cystic fibrosis at the Hubrecht Institute in the Netherlands.
We are some time off from creating malaria-resistant mosquitoes and eradicating the disease, but the discoveries and applications are incredible and could lead to slowing the rate of death from the parasite. Until then, it is important that you help reduce the spread of malaria and do your part here at home. You can join the DC Mosquito Squad in the fight and donate to the Malaria No More campaign of which we have been a proud partner since 2010. To find out more, contact your local DC Mosquito Squad or head to SwatMalaria to kindly donate.