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Argument rages over gene-altered crops

Question: I read that McDonald's will no longer be using genetically modified potatoes. Friends who just returned from London said there is a lot of opposition in Europe to all gene-altered crops, not just potatoes. What is the problem here?

Answer: Genetically modified plant varieties are created using new forms of agricultural biotechnology. The genes of seeds are manipulated in the laboratory to produce plants with desired traits, like extending the shelf life of tomatoes by turning off the plant's gene that naturally softens the aging fruit or making the tomato more cold resistant by inserting into it the gene from a coldwater fish.

This process is different from traditional breeding methods, which require years of crossing and recrossing of sexually compatible plants, and it is revolutionizing agriculture. Every few months there are new developments, including super-sweet strawberries, potatoes that absorb less fat, tomatoes that lower cholesterol, cooking oils with less saturated fat, plants with improved nutrition, coffee beans that are decaffeinated on the vine, bananas that will deliver vaccines and plants that can withstand drought, freezing temperatures and salty soils.

The major use of the technology at this time is with corn, cotton, potato and soybean crops. About 43 percent of the cotton, 4 percent of the potato and 26 percent of the corn and soybean crops in the United States are planted with varieties modified either to produce their own pesticides or to withstand weed-killing herbicides. Advocates argue that they will solve the world's food problems by creating a more abundant, more nutritious and less expensive food supply.

FRANKENFOODS: Why is McDonald's fussing about potatoes that have been engineered to produce their own insecticides that stop the crop-scourging potato beetle dead in its tracks?

Heinz and Gerber also have decided to keep their baby foods free of genetically modified substances. In Europe, major British supermarket chains have pledged not to carry genetically modified foods, which European detractors have labeled Frankenfoods, and the European Commission recently ruled that all gene-altered foods must be labeled.

The basic concern here is that such plants may reduce the genetic diversity of our food sources by destroying and replacing many older, less virulent varieties of plants (there are 50 traditional Chinese rice varieties, for example); may confer an advantage to close relative weeds through the transfer of pollen, enabling a "superweed" to overrun the modified plant and other natural vegetation, resulting in more herbicide use; may pose a threat to related species and to the ecosystems that feed from the modified plants that produce their own pesticides; may introduce allergens, toxins or bits of DNA from bacteria and viruses; and may accelerate the development of pesticide-resistant insects or plant viruses as they accommodate themselves to the new built-in genetically modified plant pesticide protection.

SEEDS OF OPPORTUNITY: Representing the other side of the debate is the U.S. House of Representatives Committee on Science. After hearing testimony from scientists representing the National Science Foundation, U.S. Department of Agriculture, Environmental Protection Agency, National Center for Genome Resources and other experts from academe and industry, the committee essentially concluded last April that there is no significant difference between plant varieties created using agricultural biotechnology and similar plants created using traditional cross breeding and that fears surrounding this new technology are not scientifically based.

Nick Smith, R-Michigan, the committee chairman, said, "Agricultural biotechnology holds tremendous potential to provide consumers safe and nutritious foods, feed a growing world population, protect the environment, aid farmers and lower costs to consumers" (see Web site http://

IN CONCLUSION: Despite the promise of genetically modified plants, misgivings about their safety, usefulness and social consequences are growing. European concerns have led to major protests, mainly in Britain and France, demanding the banning of such foods or, at the minimum, the labeling of these products.

In contrast, U.S. criticism of this new agricultural biotechnology has been comparatively muted, but it is likely that the overseas trumpeting of the danger and "scientific adventurism" of genetically modified plants will soon be heard more loudly here. This will surely spell trouble for some of our biotech companies, researchers and farmers, and it may curtail the realization of the potential social and humanitarian benefits of this new technology.

On the other hand, a wake-up call would stimulate more careful national consideration and debate about what could be one of the most important issues of the 21st century.

Patrick J. Bird, dean of the College of Health and Human Performance, University of Florida, draws on a database of more than 3,800 medical, health and fitness journals in preparing answers to questions in his column. Write with questions to Dr. Bird, College of Health and Human Performance, University of Florida, Gainesville, FL 32611. Access the Keeping Fit Web site at http://