Researchers from Oxitec, a British biotechnology company, have developed genetically-altered mosquitoes in an effort to quell mosquito populations and prevent the spread of diseases. Now, the U.S. Food and Drug Administration (FDA) is considering releasing these genetically modified mosquitoes in the Florida Keys.
Mosquito-borne diseases such as malaria, Dengue Fever, Chikungunya and Yellow Fever, claim the lives of more than one million people each year and have plagued humans for centuries. The diseases are spread when an infected female mosquito bites its victim. When female mosquitoes bite, they inject anti-coagulants to keep the blood flowing as well as some of their own saliva, which could carry viruses and parasites.
The cycle of disease can be interrupted by killing the mosquito before it bites, isolating the infected from the uninfected population and vaccinating to prevent diseases. Physical barriers, such as mosquito nets, can also be used. In the United States, insecticides are typically used to control the mosquito population. However, more and more mosquitoes are becoming resistant to these methods.
The researchers at Oxitec focus on manipulating the genome of the Aedes aegypti, one of the species known to serve as a vector for several diseases. The company has managed to modify the part of the mosquito’s gene that will kill their offspring before they grow out of the larval stage. Also, tests have been conducted on wild mosquito populations in Brazil and the Cayman Islands. Oxitec has stated that the tests were successful, but public doubts and misunderstandings about genetically modified organisms may prevent the FDA from releasing the mosquitoes in the Florida Keys.
Genetic modification roots from the Neolithic Period, when the first farmers used artificial selection to breed more desirable plants. Nowadays, researchers use genetic engineering to directly change an organism’s genes, which does not include plant and animal breeding. There is a lot of controversy on the subject, much of which revolves around introducing new DNA into the environment. Many opponents of genetically modified organisms are concerned with horizontal gene transfer, through which DNA can be transferred from one organism to another. Introducing new genetic material could lead to issues such as antibacterial resistance or cancer.
In order to prevent the introduction of altered DNA into the human bloodstream, the company says that only male mosquitoes will be released. However, in the unlikely event that a genetically modified female mosquito does manage to bite a human being, laboratory studies have shown so far that the mutated gene is relatively harmless in other animals.
Even so, critics claim it would be nearly impossible to guarantee that all the female mosquitoes would be entirely removed; regardless of how rigorous the process is, a few are bound to be overlooked.
Furthermore, there have been no guarantees that the altered DNA will affect humans. Decisions about eliminating or reducing a species so ingrained into the ecosystem also brings up the question of how it would affect the environment. Mosquitoes play a major role in the food chain as well as in pollination. The hole left by reducing the population of mosquitoes will most likely result in another species taking its place, and ecologists are still unsure of which organism it will be and whether or not we will be better or worse off.
Currently, Oxitec and the Florida Keys Mosquito Control District are working together to inform the Florida Keys community about the program. The modified mosquitoes are planned to be released in Key Haven in Key West, and if it receives the FDA’s approval, the plan will start in early 2015.
