Fears multiply over growth of genetic farms

THE number of sites planted with genetically-engineered crops in the UK has more than doubled in the past two years, according to records kept by the Department of the Environment, which monitors such "releases".

There are 182 sites in the UK where transgenic crops are being grown - of which 96 have started since 1997.

The sites are spread throughout the UK, including both Wales and Scotland, though many are concentrated in Cambridgeshire and Norfolk.

Some of the present trials have been up and running since 1993.

The Government set up its present registration system, under which companies and research organisations must request permission before releasing any transgenic species into the environment, in 1992.

The "releases" are monitored by ACRE, the Government's Advisory Committee on Releases to the Environment, which considers each application.

Earlier this year ACRE "named and shamed" a number of companies, including the multinational Monsanto, for failing to keep to the experimental procedures they had laid down.

John Beringer, the committee's chairman, said such measures were "worth many times more than fines."

In almost every case, the crops in the offending experiments were dug up, and the areas treated with paraquat.

The experiments now underway vary from 10,000 square metre plots of crops such as sugar beet, which have an extra gene making them resistant to a particular herbicide - being run by the huge multinational Monsanto, which already grows such crops commercially in the US - to wheat "containing genes to improve dough elasticity" so that it will make tastier bread.

The latter experiment is being done in a tiny 50-metre square patch by the John Innes research centre in Norwich.

The concerns of protesters are actually the same as those of ACRE, and of the scientists who are carrying out the experiments: that the test plants might somehow cross-fertilise, so that the inserted genes - say, conferring resistance to herbicides - will reach the plants such as weeds they could not otherwise reach.

That could mean make the problems of weeds worse, rather than better, because new herbicides would be needed to wipe them out.

However, earlier this week two scientists from the University of Reading's department of agricultural botany published a study in the science journal Nature, suggesting that the chances of such "transgene movement" is low. They studied oilseed rape plants along the Thames, comparing its wild habitats with commercially produced ones.

They concluded that the potential for genes to cross between cultivated and wild species is low, and would only happen slowly - but that that could change "if the transgene confers a significant selective advantage".

Anyone familiar with the principles of evolution will recognise that that comment carries a veiled warning. A herbicide-resistant gene carries an obvious selective advantage to any weed that manages to acquire it.

What researchers are still trying to ascertain is how easily that could happen through cross-fertilisation. At present, the indications are that the chances are remote.

But not every experiment runs smoothly.

In 1994 the Oxford-based Institute of Virology ran into problems when it tested a genetically-engineered pesticide containing a virus which was enhanced with scorpion venom. Its intention was to kill off caterpillars eating cabbages.

But the trial descended into near-farce when the virus was found to be contaminated with the "wild" version.

Soon afterwards the head of the institute, David Bishop, left his post.