Target Malaria is a nonprofit research consortium working to develop gene drive technologies to control the mosquitoes that transmit malaria in sub-Saharan Africa. It is led by Austin Burt, a professor of evolutionary genetics at Imperial College London.

Gene drives operate by using CRISPR (clustered regularly interspaced short palindromic repeats) to insert a genetic modification into a population and spreading it at higher-than-normal rates of inheritance. Offspring from an organism carrying a gene drive inherit the drive from the engineered parent on one chromosome and a normal gene from the other parent on the other chromosome. During early development, the CRISPR drive cuts the other copy and replaces it with a copy of the drive, producing an organism with two copies of the genetic modification. Thus, while a mutation spread through Mendelian inheritance can propagate to only 50% of descendants with each generation, a modification spread through gene drives (or "super-Mendelian" inheritance) is passed on to virtually all descendants within a single generation (Scudellari 2019).

Two applications of gene drives to the control of malaria have been proposed. One is to modify the relevant mosquito species to make it incapable of carrying the malaria parasite. The other is to significantly reduce the population of those mosquito species (Open Philanthropy 2017a). Once the gene drives are released, the relevant mutation could be propagated through the entire population of interest in a period of just a few years. In 2016, a group of researchers at Imperial College and other universities genetically engineered the Anopheles gambiae mosquito—the primary mosquito species that spreads the malaria parasite—rendering it capable of passing the genetic modification to over 99% of offspring (Hammond et al 2016)....

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