GM mosquito pilot abandoned as officials admit it did not work

Millions of genetically modified insects were released on Grand Cayman but now officials have said they will no longer fund the project 
Millions of genetically modified insects were released on Grand Cayman but now officials have said they will no longer fund the project  Credit: Scott Camazine / Alamy 

Plans to use genetically modified mosquitoes to rid the world of diseases such as malaria, dengue, yellow fever and zika have faltered after officials admitted that a major pilot had not worked.

The British company Oxitec, which was originally a spin-off from Oxford University, engineered a line of insects whose offspring were unable to grow into adulthood, causing the population to crash.

Millions of the mosquitoes were released at the British Overseas Territory of Grand Cayman over the past two years but last week the Environmental Health Minister Dwayne Seymour admitted ‘the scheme wasn’t getting the results we were looking for’ and would not be continued.

Speaking at a Finance Committee meeting, Mr Seymour said that when the contract formally ends on 31 December, that will be ‘the last you hear about Oxitec being paid by government’.

The minister said that Oxitec had suggested a different kind of genetic modification, but the  Mosquito Research and Control Unit (MRCU) on Cayman were concerned that it could put islanders at risk.

Concerns have been raised that the approach could make diseases worse by reducing immunity to the more serious forms, as well as spreading antibiotic resistant bacteria into the environment.

Earlier in the year a Freedom of Information Request by the campaign group GeneWatch UK uncovered a briefing paper showing there had been ‘no significant reduction in the abundance of mosquitoes in the released area.’

They also discovered that the numbers of female mosquitoes, which can bite and spread disease, had increased.

Dr Helen Wallace, Director of GeneWatch UK, warned that spending money on new technologies was wasting money and putting lives at risk by diverting limited resources.

Locals also objected to the release and launched legal proceedings to stop the project, although judges later ruled it could go ahead.

However MRCU Director James McNelly said the collaboration has been positive and that work would be continuing over the next few months to assess the efficacy.

“As intended, this programme provided both Government and Oxitec with valuable information that we can use going forward,” Dr McNelly said.

“The project has given us valuable insight into how Oxitec’s approach might be integrated with our conventional tools.”

A spokesman for Oxitec said the company and MRCU had 'mutually agreed' to cease the release of the mosquitoes on November 5.

"The results of this research collaboration are currently being analysed by scientists," added the spokesman.

"While the steering committee has yet to finalise its evaluation of the data, the early indications are that the joint intervention achieved positive suppression results."

Pilots of genetically modified insects are also continuing elsewhere. In September the government of Burkina Faso granted Target Malaria permission to release 10,000 sterile male mosquitoes.

Imperial College also demonstrated this year that it could cause crashes of populations of mosquitoes using gene drive technology.

However the London team said it would be at least five to 10 years before they would consider releasing the insects into the wild.

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