[MUSIC] This case study has to do with genetically modified mosquitoes. There are, of course, many mosquito-born viruses including West Nile, Chikungunya, Zika, Dengue. And these are all carried by one particular mosquito. Some of them are carried by other mosquitoes as well, but the main culprit, in many cases, is Aedes aegypti. And as Aedes aegypti's range expands, due to climate change, it's also importing those diseases in that range. Of course, travelers returning from places where these diseases are endemic can also carry disease. Oxitec is a company in the UK, whose work is based on research from Oxford University. They've developed a genetically modified mosquito that they hope will in fact reduce mosquito populations, in particular, Aedes aegypti. So far, they've done field testing in Brazil, the Cayman Islands, and in Panama. And they're currently planning testing in Florida, in the United States and in India. The technology, the mosquitoes, have in them a gene that, when expressed, gums up the transcriptional machinery of required or essential genes, such that the organism can't survive. While they're producing the mosquitoes in their facility, they produce them in the presence of tetracycline, which binds up the gene product so that it can't interfere with the transcriptional machinery and the mosquitoes can, in fact, breed. So once they have manufactured these mosquitoes, bred these mosquitoes, they take the males only and the males don't bite, females bite. They take genetically modified male mosquitoes and release those to breed with the wild Aedes aegypti population. So when a Oxitec mosquito mates with a wild Aedes aegypti female, the offspring do not have any tetracycline on board, and therefore the tTAV protein is expressed, ties up the transcriptional machinery for the essential genes and the mosquitoes die. So again, you have the Oxitec male mosquitoes breeding with a wild female population, Aedes aegypti, and the offspring die. So, in this way, it's hoped that the wild population will, in fact, go down. So I mentioned that there's currently underway planning for a trial in the state of Florida in the United States. The Food and Drug Administration, one of our Federal governing bodies, has issued a report stating that such a trial would have no significant impact on the environment. Oxitec has been working with the Florida Keys Mosquito Control District. The keys are a series of islands off the very tip of the bottom of Florida. And, as part of this process, in November of 2016, they held a couple of referendums. So they asked the populations, both of Key Haven, specifically, which is a small area in the keys within Monroe County. Key Haven is where they want to have their initial release, their test release of Oxitec mosquitoes. They asked Key Haven residents specifically and then they asked the broader population of Monroe County, which is the county in Florida where Key Haven sits. So as it turned out, the residents of Key Haven voted no. We don't want the trial here. Whereas the broader population of Monroe County voted yes. So what are the benefits and harms of such a release which again has already taken place in a number of places globally? So here's some benefits and some harms. So some of the benefits are, that if you decrease the number of Aedes aegypti, you will decrease the level of disease. You'll also decrease insecticide use, you won't have it as much in theory, spraying of insecticides to reduce mosquito populations because you're doing it in this CINBIO, facilitated biological way. If you're reducing disease, you will, again, as with the other SMN case study, have improved public health generally. And therefore, presumably, economic benefits from having more healthy people. And presumably there are some commercial benefits to Oxitec. What are the harms? Again, the FDA said that there was no significant environmental harm anticipated, but members of the public remain with concerns. Are there concerns for the ecosystem generally if you're eliminating an entire species of mosquito? And what are the effects on public trust in science, depending on sort of how the decision process plays out. Who is going to make this decision? So in the case of the recent Florida vote, the insect control body said, Key Haven said no, so we're not going to do it there, but we're going to find another in the keys to do it. So that remains to happen, but who ultimately gets to decide? Is it the people who would be mostly directly affected, the people living in the area where the mosquitoes would be released? Is it the county? Is it the state? Or does the federal government have a role to play or private companies have a role to play in making that ultimate decision about whether or not to release genetically modified mosquitoes? As with before, we ask questions about how to weigh the benefits against the harms, especially when there's a lot of unknown with regard to both. And what does the distribution of benefits and harms look like?
