By Zunera Parekh
Many diseases around the world affect people drastically, however, malaria is one of the
most potent and deadly of them all. Researchers have decided to combat this disease by fueling their efforts into a study that could potentially help eliminate malaria-ridden mosquitoes once and for all: a genetically engineered fungus with harmful spider toxin. Genetic engineering is using direct and indirect methods to manipulate the genetic makeup of an organism. In this genetic engineering study, researchers will compare the effects on mosquito populations with the engineered fungus, non-engineered fungus, and no fungus to understand to what extent the spider toxin plays a role in the already harmful fungus.
Malaria is prominent in most locations around the world, specifically third-world ones
such as Burkina Faso where researchers came together to conduct a real-world fungus study.
While some were hesitant about placing the study in Africa, as it would then feel like an
experimental site (Stein), there is a clear positive correlation between areas of poverty and
increased risk of malaria. This fungus is a necessity for not only the people there but generally around the world. Around 435 million people died in 2017 due to malaria, and 87 countries were affected in total (Saey), demonstrating the harsh and widespread effects of malaria and the urgency to find a solution once and for all. Malaria comes from mosquitoes, who transfer microscopic parasites (an organism that lives in another organism and takes away its nutrients and comfort) from their saliva into human blood. While there are many steps to be taken against this disease as it affects the majority of the world, recent science and biology can push the study to help people in a faster and more effective manner against malaria.
Since malaria is so widespread, finding an immediate solution will prove to be a
challenge. As a result of this, researchers have had to resort to innovative strategies because they wanted to ensure they could wipe out large populations of mosquitoes-their starting point being a fungus called Metarhizium pinghaense. This fungus is known for killing mosquitoes, however, the killing process works in an elongated and steady manner as the mosquitoes do not pick up enough spores needed to prove harmful to them, and have plenty of time to continue spreading malaria (Vogel). The researchers needed to find out a way to make the fungus more lethal to kill more mosquitoes in a faster amount of time which would ultimately slow down the transfer of malaria. This idea introduced the use of the spider toxin, Hybrid, which was approved by the EPA (Environmental Protection Agency) and was collected from the Australian Blue Mountains funnel-web spider (Collins). Scientists gave the strain of the fungus the spider-venom gene, and it successfully demonstrated in a lab that it was far more lethal than just the fungus’s effects as it took fewer spores to kill the mosquitoes and therefore slowed the spread of malaria a lot more effectively (Vogel). While the innovation did prove a success in the lab, scientists needed to take
this one step further to ensure this new genetically engineered combination would prove useful in the real world, despite its potential limitations.
The newly engineered fungus was studied and experimented on in a real-world situation
in Burkina-Faso, a small village in western Africa where malaria is especially prominent. The
goal of this study was to ensure that the newly engineered fungus has more of an impact than just the fungus itself on the mosquito population to eliminate more of them even faster. Researchers built a large center to conduct these studies called the “MosquitoSphere” and were prepared to start testing. They divided this center into huts to test each group: one group was with the engineered fungus spores, one with the non-engineered fungus spores (no spider toxin, in order to compare the effects of the spider toxin and no spider toxin in the fungi on the populations), and one without any spores (the control group that researchers could compare results with). The first step of the study was to ensure female malaria-ridden mosquitos had a place to rest after feeding so they could pick up spores. To accomplish this step they soaked a black cloth in each hut with sesame oils for that function, and to help the spores stick to the cloth as well (Saey). In each compartment, they released 1000 male mosquitos and 500 female mosquitos, and in two nights every week would give them a calf to feed on (Vogel). The female and male mosquitos first mated, and then the females would use the blood from the calves provided to help support their eggs to start the new generation. Then, they would rest on the black sheets with/without spores (depending on which hut they were in) after feeding, and they would pick them up when resting there, potentially causing the effects intended by the scientists (Stein). These steps were
taken to ensure the study was as close to a “real-world” simulation as possible.
The results of this field study were exactly what the scientists had predicted for each
variable group. Newly hatched mosquitoes were counted as the following: 436 mosquitos in
Generation One and 455 in Generation Two for the non engineered fungus (no spider toxin in the fungus), 921 mosquitos in Generation One and 1,396 in Generation Two for no fungus (control group), and finally 399 mosquitos in Generation One and 13 in Generation Two for the engineered fungus (Saey). This data unpacks a plethora of information that the scientists were looking for when conducting this real-world experiment to understand the differences between the three groups in the “MosquitoSphere.” The numbers of the “no-fungus” huts made sense with the data. The female mosquitoes had the liberty of giving birth as much as they could since no stimulus or variable was preventing them to do so. The main data lies in the difference between the numbers of the non engineered fungus and engineered fungus. First, by taking a look at the non-engineered fungus numbers and comparing that to the number of newly hatched mosquitoes with no fungus, it is clear that the fungus itself (with no spider toxin) can play a part in decreasing the population--455 mosquitos for non engineered versus 1,396 for no fungus (Saey).
However, the true effects of the genetically engineered fungus are displayed in the data as fewer mosquitos survived in the second generation with the spider toxin fungus than the non
engineered one. Only 13 mosquitoes survived in Generation Two for the engineered fungus, and 455 survived for the non-engineered fungus. This drastic difference explains that while the fungus itself can technically evoke some damage, the added spider-toxin greatly strengthens the fungus by allowing it to nearly eliminate the population more effectively.
While researchers were pleased with these results, they realized that there are a lot more
steps to be taken as the experiment was still conducted in a somewhat “artificial” simulation of the environment (Saey). While some are looking to the future and planning to incorporate this new “weapon” into future insecticides and other applications, some are more skeptical and cautious when it comes to the usage of this discovery. Dana Perls of Friends of the Earth (an environmental group), states that this genetically engineered fungus could potentially cause harm in ecosystems and bring possible negative public health impacts (Stein). She advises using this cautiously, as she believes genetic engineering could bring negative consequences to the world as a whole, especially when dealing with widespread diseases, such as malaria, which contradicts how others see this as an extremely useful tool for the future.
Researchers all over the world are in anticipation of this breakthrough in genetic
engineering tools as it will solve a lot of problems in the future for the people who are so
affected by malaria, especially those in third-world countries and poverty. The experimental
study in the “real-world” situation may have given a better idea to see the effects of engineered, non-engineered, and no fungus on the mosquito populations, but there is a lot more research to be done before this can be used. This is merely the tip of the iceberg in this scientific genetic engineering process, as others will voice their concerns on the negative consequences the genetically engineered product could potentially bring to the environment and ecosystem. Genetic engineering breakthroughs in science may be an advantage that ultimately allows humankind to combat lethal diseases and other cases.
Works Cited
Collins, Francis. “Transgenic Fungus – NIH Director's Blog.” National Institutes of Health, U.S.
Department of Health and Human Services, directorsblog.nih.gov/tag/transgenic-fungus/.
Saey, Tina Hesman. “A Fungus Weaponized with a Spider Toxin Can Kill Malaria Mosquitoes.”
Science News, 8 Aug. 2019,
www.sciencenews.org/article/fungus-weaponized-spider-toxin-can-kill-malaria-mosquito
es.
Stein, Rob. “Scientists Genetically Modify Fungus To Kill Mosquitoes That Spread Malaria.”
NPR, NPR, 30 May 2019,
www.npr.org/sections/goatsandsoda/2019/05/30/727884309/scientists-genetically-modify
-fungus-to-kill-mosquitoes-that-spread-malaria.
VogelMay, Gretchen, et al. “Fungus with a Venom Gene Could Be New Mosquito Killer.”
Science, 30 May 2019,
www.sciencemag.org/news/2019/05/fungus-venom-gene-could-be-new-mosquito-killer#.
