Scientists have created mutant mosquitoes to combat malaria. However, the method used to tweak the genes could revolutionize the way genes are manipulated, allowing scientists to save other species, as well.
California researchers produced a strain of mutant mosquitoes carrying genes that block the transmission of malaria, not just from host to victim, but also in between mosquitoes, as well. Researchers hope such mutant mosquitoes will breed with other members of their species and produce offspring that cannot spread the disease. Such genetically modified mosquitoes will be released in the wild to ensure the genes are spread to others of their species, and eventually spawn mosquitoes that are incapable of hosting or transmitting malaria.
Though such techniques have been attempted before, this time, modern science has improved the method by leaps and bounds. Using gene-editing, a genetic engineering technique in which DNA can be inserted, replaced, or deleted from a genome, on a species called Anopheles stephensi that spreads malaria in urban India, researchers at the University of California were able to create an entirely new variant of the mosquitoes, which could eventually help to eradicate malaria, reported Fox News.
What makes the method of gene editing to make malaria resistant mosquitoes promising is the probability of survival of genes in subsequent generations. The experimental batch of mutant mosquitoes was created using a technique called “gene drive.” If the technique pans out, scientists are confident they can alter the genetics of populations of insects and certain plants and animals faster than Mother Nature ever could, reported the Daily Democrat.
The previous attempts had a rather poor chance of success. This is because genes have a 50-50 chance of being inherited. However, using the “gene drive” technique, researchers created a strain of mosquitoes that could pass a specially engineered malaria-blocking gene to about 99.5 percent of their offspring, reported CNN. Essentially, the DNA inserted into the first batch of mosquitoes would assuredly survive subsequent batches of mosquitoes, without getting destroyed during multiplication of the species, said Anthony James, Distinguished Professor of molecular biology & biochemistry and microbiology and molecular genetics at University of California’s Irvine campus.
“This opens up the real promise that this technique can be adapted for eliminating malaria. We know the gene works. The mosquitoes we created are not the final brand, but we know this technology allows us to efficiently create large populations.”
The plan appears simple, but the scale it requires to work is gargantuan. Malaria is spread by female mosquitoes, which act as hosts for the virus. The genetically modified male mosquitoes will hopefully mate with the females in the wild and transmit the malaria-blocking genes into the local gene pool. Such a technique should hopefully infuse malaria resistant genes into the entire mosquito population. Without a host to ferry and transmit it to humans, the malaria virus won’t be able to remain a global epidemic, which it is today. The key is to ensure the modified genes survive subsequent generations of mosquitoes, said University of California-San Diego biologist Valentino Gantz.
“It can spread through a population with great efficiency, increasing from 1 percent to more than 99 percent in 10 generations, or about one season for mosquitoes.”
In the modern world, malaria is one of the most potent killers. Every year, malaria kills more than half a million people a year, mostly children in Africa. There are over 200 million infections in a year. Mosquitoes bite an infected person, and then spread the virus to many more. Despite the use of insecticides, simple bed nets that keep mosquitoes at bay remain the ideal solution.
If the “gene drive” technique shows promise, it could help infuse tweaked genes into plants and other species. Those species with poor genetic variation are often susceptible to mass-extinction. By artificially infusing tweaked genes, the species could be saved, hope the scientists.
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