Destroying Malaria One Mosquito at a Time
In 2015, scientists successfully tested the first Gene Drive mosquito in Saccharomyces (a species of yeast) and Drosophila (a genus of small flies). This idea isn’t new, the idea of using Gene Drives started in the 1940’s, but Gene Drives are made a possibility because scientists now have the genetic tools used to create Gene Drive mosquitoes more efficiently. Gene Drives are genetic systems that help abolish wild mosquitoes that carry Malaria and other life-threatening diseases. When Gene Drive mosquitoes mate with a wild mosquito, the Alter gene of the wild mosquito gets removed by Cas9 (which is an RNA-guided DNA Endonuclease enzyme) and then copies the DNA of the Gene Drive mosquito. After this process is complete, the offspring of the two parent mosquitoes with have a 50% chance that nearly all offspring will inherit the altered gene, which causes this gene to rapidly spread through the entire population. Professor Austin Burt of Imperial College London, first proposed this idea of cutting the DNA of wild mosquitoes in order to reduce the spreading of diseases.
Gene Drives can spread genetic alterations through specific wildlife populations of mosquitoes and finally destroy Malaria. These tiny mechanical mosquitoes can save over half a million lives in many different countries. But a new Genome Editing tool called CRISPR/Cas9 was introduced by scientists at the Wyss Institute, Harvard Medical School, Broad Institute of Harvard, and MIT. The CRISPR system allows scientists to insert, delete, replace, or regulate genes in many different kinds of species. The scientists drew their inspiration from a form of bacterial self-defense. Bacteria use the system CRISPR to store DNA from invading viruses, so they recognize the virus when they return. Using this system makes it much easier to cut the DNA of wild mosquitoes. It is a possibility to use Gene Drives on different animals and plants. For example, if one mosquito is carrying a copy of the alter gene, there will be a 50% chance the offspring will inherit the gene. But if they use a Gene Driver, with the Alter Gene, Guide RNA and the Cas9 enzyme, there will be more than 50% chance that nearly all offspring will inherit the gene.
If there is going to be a release of Gene Drives, scientists are required to get the approval by the Food and Drug Administration (FDA) for animals and other agencies for plants and insects before Gene Drives are allowed to be tested in the wild. Gene Drives have the potential to become a success, if they are not rejected by government agencies. Let’s just hope that we can destroy Malaria one mosquito at a time.