America: Open-air test on GM Mosquitoes in Florida Keys soon
Recently, the Researchers have reported initial signs of success from the first release into the environment of mosquitoes engineered to pass a lethal gene to their offspring, killing them before they reach adulthood. The results could herald an age in which genetically modified insects will be used to help control agricultural pests and insect-borne diseases like dengue fever and malaria. Authorities in the Florida Keys, which in 2009 experienced its first cases of dengue fever in decades, hope to conduct an open-air test of the modified mosquitoes as early as December, pending approval from the agriculture department.
But the research is arousing concern about possible unintended effects on public health and environment, because once genetically modified insects are released, they cannot be recalled.
Here is a background on RIDL technique used for Malaria Control by GM Mosquitoes
RIDL refers to “release of insects carrying a dominant lethal” and is a technique of insect control by using the GM technique.
The more popular technique is known as “Sterile insect technique”. This is a technique of Biological Control, in which sterile insects are released. since, most diseases such as Malaria / Dengue etc. are spread by the Females, the sterile males are released. These sterile males compete with the wild males for females. If a female mates with a sterile male, it can have no offsprings, and thus next generation would be sterile. This technique was first successfully used to eradicate the screw worm fly (Cochliomyia hominivorax) in America.
The males are sterilized usually by the radiation. The American entomologists Dr. Raymond C. Bushland and Dr. Edward F. Knipling, who developed this technique were given world food prize in 1992.
Recently, the recombinant DNA technology is being used to create Genetically Modified insects and this technique is called RIDL (Release of Insects carrying a Dominant Lethal). This technology is under development by a company called Oxitec, which is an spin off of the Oxford University. In this method, the Dominant lethal gene is introduced in the insects.
This technique, in various forms and methods is now being researched by the scientists amid words of cautions that it may lead to unforseen results also. Malaysia is going to be the first country in Asia to use these GM mosquitoes to battle dengue via the RIDL technique. The health ministry of the country has planned to release 2000-3000 GM mosquitoes in some areas. If successful, it can be a good achievement in tackling both Dengue and Malaria.
The first strategy was tested successfully in Malaysia during 2007-2008. The second strategy, developed by a group funded by the Gates Foundation, was in 2010, being tested in outdoor cages in some parts of Mexico.
The technique of Population suppression is favoured over the disease resistance technique and may show the results sooner.