Fears that feeding genetically modified crops to animals could give rise to antibiotic resistant bacteria appear to be false, according to research by British scientists.
A team at the University of Leeds led by Dr John Heritage has been studying claims that antibiotic resistant genes incorporated into GM crops could cross over into bacteria in animals' guts and give rise to "superbugs". These would be potentially lethal to humans.
But in a series of experiments, Dr Heritage's team said they had so far "drawn a blank", even when they had done their best to persuade the genes to transfer into the bacteria.
Pete Riley, a food campaigner at Friends of the Earth, said the work sounded "interesting", but added: "I don't think this is the definitive piece of research."
However, Derek Burke, a former chair of the Advisory Committee on Novel Foods and Processes, which initially recommended rejecting such GM foods for animals, said: "It now looks as though the risk is less than was originally thought."
The Leeds team is investigating the behaviour of a gene called "bla", which confers resistance to the antibiotic ampicillin and is inserted alongside genes for pesticide resistance in the creation of GM crops such as maize.
GM maize made by Novartis and containing the bla gene was cleared in 1996 for sale in Europe. But in October 1998 France banned its sale and cultivation, amidst fears it could promote antibiotic resistance.
In the work, reported today in New Scientist magazine, the researchers looked to see if gut bacteria from chickens had acquired and "turned on" the bla gene after being fed GM maize. Dr Heritage also tailored the experiment to encourage that takeup, but found no activation of the gene. However, the work has not been completed.