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DNA strand
10.04.02
Science and Health:
Seeds of Conflict
More on This Story:
NATURE Article Debate

The agricultural biotechnology industry stakes its reputation on safety, and the ability to control the genes it unleashes, especially when it comes to food. So when NATURE published an article challenging established beliefs about the characteristics of laboratory-tailored plants (see Colorado State University's Web site for more on transgenic plants), it ignited a heated controversy among scientists, activists and industry groups that continues to brew today.



Last fall, UC Berkeley Assistant Professor, Ignacio Chapela and his graduate student, David Quist published a paper in the journal NATURE that essentially made two claims. First, they asserted that traces of DNA from bio-engineered corn had spread to native Mexican corn (or maize). Mexico, corn's birthplace and an invaluable genetic reservoir for crop breeders around the world, banned the planting of bio-engineered corn for fear it might harm their native varieties. Whether or not these new altered genes pose a serious threat to corn's most significant gene pool has not yet been studied.

Hear Dr. Chapela talk about the NATURE article.

It was the paper's second suggestion that prompted a barrage of criticism. The foreign genes, Chapela and Quist wrote, "seemed to have become re-assorted and introduced into different genomic backgrounds."

What this suggests is that engineered DNA had fragmented and scattered through the maize genome in an unpredictable fashion, contradicting the biotech industry's claim that these genes stay exactly where they're put.

"It was something unpredicted, and also something that the makers of this technology had been telling us would not happen," says Chapela, an assistant professor of Microbial Biology. "So there was, a lot of anxiety about it within the industry." The implication is that the new DNA in these plants could have a number of unpredictable effects, including disruption of the plant's normal functions.

A number of scientists responded immediately, criticizing Chapela's scientific methodology. "They interpreted their results erroneously, that the gene went wild and was doing things now totally unexpected like Frankenstein's monster," says Dr. Michael Freeling, Professor of Genetics in the Department of Plant Biology at UC Berkeley. He and his graduate student, Nick Kaplinsky, were among the many scientists who wrote letters to NATURE disputing the science of the original paper.

Hear Dr. Freeling talk about the NATURE article.

"Their second result in their paper, where they claimed that the transgenes were jumping around and behaving unpredictably, was based on an artifact, a mistake that I'd made myself very early on in grad school," said Kaplinsky, who had first written Chapela directly to point out what he felt was faulty science. Kaplinsky later wrote a letter to NATURE, which published his critique; the magazine quickly became a focal point for criticism and defense of Chapela and Quist's work. What was at stake in the debate was the predictability of the new gene's behavior in the genome. To do their research, Chapela and Quist used a 20-year old method called PCR (Polymerase Chain Reaction) to detect the bio-engineered DNA in the Oaxaca, Mexican maize genome. They used a younger method, only two years old, called I-PCR (Inverse Polymerase Chain Reaction) to identify where in the genome the DNA was situated. While Chapela agrees that the I-PCR method often turns up false positives, he stands by his original results.

"There's nothing that shows that I was wrong. Why should I disown it myself and recant it," says Chapela. But NATURE, felt differently. For the first time in the publication's history, they published a disclaimer for Chapela and Quist's paper that stated: "the evidence available is not sufficient to justify the publication of the original paper."

The paper also came under fire in the form of an aggressive Internet campaign on biotech-related sites, including AgBioWorld, a web site utilized by scientists. This strategy succeeded in elevating a dispute that might have only played out in the pages of a scientific journal, into public assault on Chapela and Quist's motivations and credibility.

Two of the most vocal critics denouncing the paper online were "Mary Murphy" and "Andura Smetacek", names that were later revealed to fabricated. It was discovered that one of the electronic personas came from a Washington, DC-based public relations company that worked for Monsanto, a leading biotechnology company.

"I was surprised at the strength of the attack," says Quist. He thinks the controversy over the paper had more to do with politics than science. "We're talking big politics. We're talking…big trade going on between the United States and Mexico that could be affected by this kind of information."

These UC Berkeley scientists were no strangers to the politically-charged issue of bio-engineered crops. In 1998, Chapela had spoken out against Berkeley accepting a multi-million dollar research grant from the Swiss pharmaceutical company, Novartis. Freeling, on the other hand, supported the alliance.

"I could be in the pockets of industry or not. It wouldn't make any difference," says Freeling. "I could be for or against genetically modified organisms, or believe in any political hocus-pocus whatsoever, and it wouldn't matter. The science is just bad. You can only apologize and retract."

Chapela stands by the findings in the paper and feels the public should understand more about this new technology. "Why should I not inform the public when the public is so desperate for information?" says Chapela. "Once you become convinced about something from your science, from your experience, from your knowledge then telling the public about it, I think, is part of my job."

In August, Chapela and Quist's discovery of transgenes in the corn in Oaxaca, Mexico was independently verified by the Environment Ministry of the Mexican Government. The Environment Minsistry conducted their own study that is now undergoing peer review for publication.

--Keisha-Gaye Anderson

SOURCES: "Transgenic DNA introgressed into traditional maize landraces in Oaxaca, Mexico" By David Quist and Ignacio H. Chapela, NATURE, November 29, 2001, Vol. 414, pp. 541-543; "Has GM Corn 'Invaded' Mexico?", By Charles C. Mann, SCIENCE, March 1, 2002, Vol. 295, p. 1617; "The Great Mexican Maize Scandal", By Fred Pearce, NEW SCIENTIST, June 2002, p. 14; "Biotech's OK Corral, "By Wil Lepkowski, CSPO (Science and Policy Perspectives) Senior Correspondent, July 9, 2002; THE GUARDIAN Newspapers (May 14, 2002; May 24, 2002; May 29, 2002); NEW SCIENTIST (July 6, 2002); "Monsanto--Up to its dirty old tricks again," By Jonathan Matthews, THE ECOLOGIST, May 2002, Vol. 32 No. 4

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