Malaria has ravaged the Sub-Saharan region for over 300,000 years, causing 438,000 deaths each year. Mosquitoes carry the Plasmodium parasite, spreading them from person to person with each bite. The disease typically presents itself in fever, chills, and vomiting, while the more serious infection of P. falciparum can lead to organ failure, altered blood, and death.
The war on Malaria has lasted for decades, with countries bouncing between epidemics and eradication of locally acquired Malaria cases. As an example, Kyrgyzstan eliminated malaria in 1961, but 25 years later, the disease made a comeback. Without constant national attention on health and prevention, malaria can quickly take root again.
In 2002, Kyrgyzstan led a new campaign against Malaria, backed by major organizations such as the World Health Organization (WHO) and the U.S. Agency for International Development (USAID). In November of 2016, WHO bestowed a certification of malaria elimination on Kyrgyzstan for being malaria-free for three consecutive years.
However, the threat of malaria always looms. How can we eradicate malaria once and for all?
Researchers want to create mosquitoes genetically modified to be incapable of transmitting malaria. After releasing these into the wild, they hope the mosquitoes will pass on these genes to the rest of the mosquito population, until all mosquitoes are immune from transmitting malaria.
Recently, researchers at UC Irvine and UC San Diego successfully inserted DNA code into Anopheles stephensi mosquitoes, common carriers of malaria. These mosquitoes are incapable of transmitting malaria, and thanks to the gene drive method, will pass on this edited gene to 99.5% of their offspring. Once introduced to the wild, this dominant gene should quickly spread throughout the mosquito population.
UCI Professor Anthony James and his team used a technique called CRISPR to modify the mosquito’s genome. CRISPR allowed the team to cut the original DNA and insert modified mouse genes to prevent malaria parasites from moving through the body.
Although still far from a finished product, Anthony James stated that “this opens up the real promise that this technique can be adapted for eliminating malaria.”
Despite the possible benefits of CRISPR, genetic engineering has also set off an ethical debate. Editing a species may carry unintended consequences. Once the modified mosquitoes have been released in mass, the decision is irreversible.
Some fear that the Plasmodium parasite will adapt to the new genes in negative ways. Others fear the ramifications of genetic engineering as a whole. Proponents of the slippery slope argument say that increased genetic modification may spread harmful genes capable of wiping out entire populations. In addition, CRISPR is a step towards human genetic modification, a huge moral gray area.
In the end, humanity must weigh the costs and benefits of genetic engineering before making any decisions. Perhaps in the case of malaria, the hundreds of thousands of deaths justify a radical response.
CRISPR has the potential to revolutionize the future of disease control. The same technology could be applied to Zika, Dengue Fever, and Lyme Disease, to name a few. As UC San Diego professor Ethan Bier put it, “the ability of this system to carry large genetic payloads should have broad applications to the future use of related CRISPR-based ‘active genetic’ systems.”