Smelling rats in GMO conspiracy theories
05.apr.99, Doug Powell, Farm and Country
After an internal review of the data, it emerged that not only had Dr. Pusztai ignored the conventional route of scientific peer review, he had been sloppy in designing the experiment and, most importantly, was talking about the wrong potatoes when he appeared on television.
05.apr.99, Doug Powell, Farm and Country
On Feb. 12, U.S. Chief Justice William Rehnquist dispatched Bill Clinton's shenanigans from stately Senate trial to dirty jokes, Monica makeovers and the inevitable Barbara Walters interview, leaving conspiracy theorists in the lurch. But not for long. That same day, a group of 20 international scientists released a letter supporting the work of Dr. Arpad Pusztai, who allegedly found that genetically engineered food could, in feeding studies, harm rats. The British press was consumed by the new allegations, charging cover-ups, political payoffs and every unseemly human behaviour to anyone remotely involved in the biotechnology of food. The true story, however, is more about the role of trust in the food supply than any scientific insight. On August 10, 1998, Dr. Pusztai of the Rowett Research Institute in Aberdeen, Scotland, reported that after feeding five rats for 110 days potatoes genetically engineered to contain one of two lectins that are known to be toxic to insects, some of the rats showed stunted growth and impaired immune systems. Dr. Pusztai's mistake was that he chose the World in Action television program, rather than a scientific forum, to broadcast his uncorroborated results. After an internal review of the data, it emerged that not only had Dr. Pusztai ignored the conventional route of scientific peer review, he had been sloppy in designing the experiment and, most importantly, was talking about the wrong potatoes when he appeared on television. By Aug. 12, he was suspended and subsequently forced to retire. No matter. On Feb. 12, 1999, the letter appeared, charging that Dr. Pusztai had been unfairly treated and, more importantly, that the scant data revealed a more menacing problem. Because there seemed to be more damage in rats that had been fed the genetically engineered potatoes than in a control group that was fed ordinary potatoes with the lectin mixed in, perhaps the process of genetic engineering itself, in particular the use of the 35S cauliflower-mosaic-virus promoter, was to blame. The 35S promoter is widely used in the genetic engineering of plants to turn specific genes on and off; therefore, the argument goes, all such plants pose a risk. Maarten Chrispeels from the University of California, San Diego, one of the researchers who initially supported Dr. Pusztai, is now, as quoted in the Economist magazine, particularly skeptical. Potatoes themselves are full of poisonous chemicals in quantities that vary depending how the spuds are grown, a phenomenon known as somaclonal variation, and must therefore be uniformly grown for any feeding trail to be informative. Further, rats are not particularly partial to raw potatoes, and their diet must be supplemented. As well, the allegations about the 35S promoter are not new. In fact, one of the signatories of the Feb. 12 letter is Dr. Joe Cummins, formerly at the University of Western Ontario in London, whose views on the potential dangers of 35S have been well-circulated on the Internet. Regulators in Western countries already demand evidence that the 35S insertion is stable and well-characterized. And other feeding experiments involving the 35S promoter have simply not found the problems described by Pusztai and supporters. That such allegations were amplified in the U.K., still stumbling from mad cow disease and a regulatory system viewed as impotent, is not surprising. But in Canada? On Feb. 20, the Globe and Mail announced with great fanfare in a feature by Gwynne Dyer (with the oh-so-original title Frankenstein Foods) that, on Feb. 12, the first evidence of health problems connected with GM foods surfaced in Britain. Dyer's recycled analysis of genetically engineered foods was rife with errors and innuendo that conveniently ignored any key information that was inconsistent with his conspiracy manifesto.The most important omission was this: The genetically engineered potato created by Dr. Pusztai never would have been approved for sale in the U.K., Canada or the U.S. Unfortunately, the line about "the first evidence of health problems" has already resurfaced in another Globe article about genetically engineered food. The agricultural products of biotechnology are increasingly grown by North American producers because they are safe, and in many cases yield a good return on investment for farmers. To imply, as Dyer and many others do, that North American farmers and consumers are unwitting dupes of political influence and technological determinism is, among other descriptors, arrogant. Work conducted in my laboratory has shown that the No.1 reason Ontario farmers choose to grow genetically engineered corn is to try it out for themselves - to see if the technology worked as promoted on individual farms with individual needs. Thankfully, that point was not lost on John Greenwood of the National Post, who also wrote on Feb. 20 in an article about the so-called terminator gene that "farmers should take comfort in the fact that they will have the final say." Douglas Powell is an assistant professor in plant agriculture at University of Guelph. His new book, "Reclaiming Dinner," will be published this summer