Digging deep for answers

Teagasc’s decision to carry out field tests on GM potatoes has angered the ‘Green Food Ireland’ lobby but the critical issue is that it is not planning to conduct toxicity tests, writes Dr Oliver Moore

‘THIS new GM potato research should include tests on toxicity, but it probably won’t. You can imagine how popular this type of testing is after Pusztai’s dismissal.”

So says Dr Paul Dowding, retired plant pathologist, from Trinity College Dublin. Dowding is published in numerous peer-reviewed academic journals, from 1968 onwards, in plant pathology, pollen, and air pollution.

Arpad Pusztai was sacked from the Rowett Institute, which specialised in food safety research, in Scotland in 1998. He had just made two TV appearances where he claimed that his own studies were pointing to toxicity in GM potatoes.

The research, published in The Lancet in 1999, was subject to much controversy at the time. Unusually, it was triple peer-reviewed before publication. It was then “with breathtaking impertinence” re-reviewed by the Royal Society — voice of the scientific establishment in Britain — according to The Lancet’s editor Richard Horton. Horton was subject to what he claimed was a career-threatening phone call after publication.

Pusztai, author of more than 300 peer-reviewed academic publications, and one of his co-authors, Dr Stanley Ewen, found themselves ostracised from the mainstream scientific community and unable to find work.

According to Paul Dowding, Pusztai’s work tested the “toxicity or otherwise of the new potato. You have to remember that potatoes are very poisonous plants apart from the tuber, and just exposing the tuber to light can make it poisonous too.”

Pusztai’s studies involved testing a potato that had been engineered to include a lectin from snowdrop. “It was a three-way comparison involving feeding different groups of rats with balanced diets containing plain potato, or GM potato, or plain potato plus pure lectin for 110 days.”

“He looked carefully at outcomes: Blood tests, immune function, he measured organ weights, and examined the cell structure of the gut. He found that rats fed on diets with potato plus pure lectin were as healthy as those fed on diets with plain potato.”

However, says Dowding “some of the rats fed the engineered potato showed depressed immune function, altered white cell counts, damaged thymus and spleen, smaller brains, livers and testes, as well as changes in cells lining the gut. So there were things in the GM potato that were not lectin, and that had a deleterious effect on the rats’ health. That leads one to the inescapable conclusion that inserting one gene has more complex effects than just changing that one parameter.”

So will this new research by Teagasc test for toxicity? No, says, Teagasc’s head of crop research John Spink, who points out that its proposed research, part of the Amiga European project, will only “look at the potential environmental impact — good or bad — of growing blight-resistant potatoes”.

He adds that unlike Pusztai’s work “our cisgenic potato is modified with only a wild potato gene which is structurally very familiar to genes that already exist in potato and which have evolved to target only the fungus that causes blight disease”.

The worry for Dowding, however, is that assumptions on food safety are made “without looking thoroughly for adverse effects, which is highly disturbing”.

He continues: “There has been very little research into toxicity, hardly any independent toxicity testing. The regulatory authorities are satisfied with results reported by and paid for by the likes of Monsanto. I’d have serious question marks over that type of research.”

On whether there has been research into toxicity and GM potatoes since Pusztai’s work, Spink stated that “there has been some work”, citing a 2005 publication by Hermann Broll that showed “no plant-specific DNA or DNA specific for the genome alteration in the transgenic potato were detected in any organ”. Spink was “not aware of the funding source of the research”.

There are “no plans at the moment to complete additional research within the scope of the existing study”, Spink says, which means there will be no toxicity testing of the GM potatoes.

“Teagasc GM research programme has no links with any biotech industry and this study is not about developing GM potatoes for commercialisation or generating either a national or international market for GM potatoes,” he says.

Spink continues: “It would be illogical for Teagasc to undertake a research project that would or could in any way compromise existing potato production in Ireland.”

Interestingly, neither Spink nor Dowding are worried about pollen contamination and this GM potato trial, because, they suggest, potatoes have no wild relatives in Ireland and are grown from seed potatoes (ie, other potatoes) not from seeds produced on the plant.

UCC plant biologist Dr Eoin Lettice welcomes the GM trials. He says it will “add to the volume of information available on GM crops and their impact on the environment”, pointing to the irony of objections to the GM potato trial which cite the lack of research into environmental impacts.

But is science afraid to ask the really hard questions, the kind that might jeopardise future funding, career paths, or relations with powerful interests? Worryingly, there is evidence that it can be, not just in the treatment of prominent scientists like Pusztai, but in the scientific research itself.

Brian Martison (Nature, 2005) found that one-third of 3,000 surveyed scientists, drawn primarily from the biological sciences, admitted to behaving unethically in their research, and 15.5% of them specifically admitted that “they had changed how they conducted an experiment or its results in response to pressure from a funding source”.

Considering how difficult such an admission would be, even in a confidential survey, this may be a conservative estimate.

This Teagasc GM potato trial differs from what was attempted by Monsanto’s with GM sugar beet in Wexford in the late 1990s. Sugar Beet has wild plant relatives in Ireland, is produced by seeds, not tubers, and thus carries a significant pollen risk. This new proposed trial, by a State agency, without corporate involvement or commercial development, is “conservative, well-designed, and tightly controlled” in the words of Dr Lettice.

But do the conservative parameters of the trial, which include no toxicity tests of the potatoes, represent something of an Achilles’ heel? And does the trial represent the very beginnings of a new direction for agri-food in Ireland, one consumers will take some convincing of?

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