To curb the spread of mosquito-borne diseases, an experiment aimed at reducing the number of Brazilian mosquitoes by releasing hundreds of thousands of genetically modified mosquitoes has not only failed, but may even create a superspecies of genetic hybridization.
In 2013, a team of Oxitec, a British biotechnology company, conducted a 27-month experiment in Jacobina, Brazil, to eliminate 90% of the mosquitoes while maintaining the genetic integrity of the mosquito population, Russia reported today.
According to RT, the overall objective of the experiment is to curb the spread of mosquito-borne diseases such as yellow fever, dengue fever, Chikungunya fever and Zhaika by releasing 500,000 mosquitoes. OX513A mosquito is a modified version of Aedes aegypti.
The scientistsidea sounds reasonable. It is reported that the principle of the experiment is to genetically modify the male Aedes aegypti to have a dominant lethal gene. When they mate with wild female mosquitoes, the gene will sterilize their next generation, thereby reducing the number of mosquitoes.
The initial results show that the experiment has a significant effect.
According to the report, initial research by Oxford Insect Technologies showed that only 3% to 4% of sterile mosquitoes survived to adulthood and were too vulnerable to reproduce, resulting in a sharp decline in mosquito populations.
However, a recent study by a team of ecologists and evolutionary biologists, Jeffrey Powell, on the effectiveness of the experiment shows that things are not going as they might have been imagined.
Over the next 18 months, the situation reversed completely: the number of mosquitoes in Jacobina returned to pre-release levels.
Powell and his team say wild female mosquitoes are beginning to experience mating discrimination by choosing not to breed with weaker GM mosquitoes. Some genetically modified mosquitoes even show hybrid vigor. Artificially introduced genes make mosquitoes stronger, and their resistance to insecticides may also increase.
However, Oxford Insect Technologies rejected this.
A spokesman for Oxford Insect Technology said the Powell teams study contained a large number of false, speculative and unconfirmed claims and refuted the mating discrimination mentioned by Powells team: of the 1 billion GM male mosquitoes released worldwide, no mating discrimination has ever occurred. Elephant.
Source: Global Network Responsible Editor: Qiao Junjing_NBJ11279