Policy Concentrates BIOTECHNOLOGY
Oxitec moves closer to releasing modified insects in Florida field trial A mosquito genetically modified to produce offspring that can’t reproduce is one step closer to being tested in a field trial in the U.S., as part of efforts to stop the spread of the Zika virus and other mosquito-borne diseases. The Food & Drug Administration concluded earlier this month that a planned field trial in Key Haven, Fla., of the OX513A Aedes aegypti mosquito developed by England-based biotech company Oxitec “will not result in significant impacts on the environment.” Oxitec is working with the Florida Keys Mosquito Control District to conduct the experiment. The company cannot legally release its genetically modified mosquitoes, however, until FDA gives a final goahead. First, though, FDA will review public comments on the company’s environmental assessment, which was released with the agency’s finding of no significant impact. It
could be several months before FDA makes a final determination. “The A. aegypti mosquito represents a significant threat to human health and in many countries has been spreading Zika, dengue, and chikungunya viruses,” says Oxitec CEO Hadyn Parry. “This mosquito is nonnative to the U.S. and difficult to control, with the best available methods only able to reduce the population by up to 50%,” he notes. Offspring from Oxitec’s OX513A mosquitoes die before reaching adulthood, thus reducing the population of this species. The company intends to release only male Oxitec mosquitoes, which do not bite, to mate with wild A. aegypti females. The OX513A mosquitoes have been tested in trials in Brazil, Panama, and the Cayman Islands, with promising results. In each case, the A. aegypti population was reduced by more than 90%, Oxitec claims.
Genetically modified Aedes aegypti mosquitoes could be part of the arsenal in the fight against the Zika virus. This, it says, is “an exceptional level of control compared to conventional methods, such as insecticides.” But some critics argue that FDA is not the appropriate federal agency to assess environmental effects. It is doing so because, in the U.S., genetically modified animals are regulated by FDA as new animal drugs. Deliberately altering the traits of a mosquito to suppress its population is “not something we should do lightly,” says Kevin Esvelt, a biochemist and leader of the Sculpting Evolution Group at Massachusetts Institute of Technology. “There might be unexpected ecological side effects,” he warns. Esvelt has expertise in developing technologies such as RNA-guided CRISPR gene drive, which can be used to alter the traits of wild populations. “At this stage we know so little about Zika that I am uncomfortable talking about the potential to use gene drive against these mosquitoes because of Zika. We just don’t know enough.”—BRITT
ERICKSON
LEGISLATION
GMO food labeling bill stalls in the Senate Legislation that would block states from requiring labels on genetically modified (GMO) foods faltered in the Senate last week. The measure, which was offered as an amendment to an unrelated bill (S. 764), would prohibit states from requiring labels on GMO foods and establish a federal voluntary labeling standard. In a 48-49 vote, the bill failed to garner enough support for the Senate to move it forward. Senate Majority Leader Mitch McConnell (R-Ky.) left open the possibility of holding a vote on the GMO food labeling legislation at a later date. Sen. Pat Roberts (R-Kan.), who introduced the legislation, and supporters of his proposal, including the food industry, are
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C&EN | CEN.ACS.ORG | MARCH 21, 2016
An increasing number of consumers want to know whether GMOs are in their food.
anxious to get the measure enacted before a law requiring labels on GMO foods goes into effect in Vermont on July 1. Other states are also planning similar laws. The food industry claims that a patch-
work of state labeling laws will be costly for companies and, ultimately, consumers. Environmental and food safety advocacy groups are calling the Senate bill’s defeat a victory for consumers, who they say have the right to know what is in their food. Roberts, chairman of the Senate Agriculture, Nutrition & Forestry Committee, is urging opponents of his proposal to work with him toward a solution. “I have been flexible and have compromised in order to address concerns about making information available to consumers,” he says.—BRITT ERICKSON
DANIEL BECERRIL/REUTERS/NEWSCOM (MOSQUITO); ERIK MCGREGOR/ZUMA PRESS/NEWSCOM (PROTESTERS)
FDA clears way for gene-altered mosquito
