Genetically modified plants and animals

You may have seen or otherwise been made aware of protests against genetically modified food, sometimes called "Frankenfoods." The title most probably comes from the story of Dr. Frankenstein, who creates a monster that could not be con­trolled. Critics fear the same for food that has been genetically modified or tampered with. What are they talking about? These are crops that have been genetically modified to include desired traits such as drought tolerance or lowered freezing level. Although some of these traits could be established through traditional breeding methods, some could not. Genetic mechanisms both speed up the process and give more control over it.

Recently, the National Academy of Sciences has determined and reported that "genetically engi­neered crops do not pose health risks that cannot also arise from crops created by other techniques, including conventional breeding."⁴⁰ It is not the method of production that should be of concern, the NAS argues, but the resulting product. There is much that the general public does not understand about so-called genetically modified food.

Strictly speaking, genetic engineering involves inserting a specific gene from one organism into another—and the function of the gene is known. On the other hand, "nearly every food we eat has been genetically modified" in the broader sense in that plants have been cross-bred for centuries.⁴¹

Chapter 17 ■ Stem Cell Research, Cloning, and Genetic Engineering 417

Cross-breeding "involves the mixing of thousands of genes, most unknown."⁴² In some cases, muta­tions are now caused by "bombarding seeds with chemicals or radiation" and seeing what comes of it. For example, lettuce, beans, and grapefruit have been so modified.⁴³

Over the last few years, U.S. farms have gradu­ally increased the amount of crops that have been genetically engineered. In 2002, one-third of the corn grown in the United States was genetically engineered. Farmers now grow "more than 79 mil­lion acres of genetically engineered corn and soy­beans, the nation's two most widely planted com­modities."⁴⁴ Of the cotton crop, 71 percent is also gei=ie-altered. "Nearly two-thirds of the products on American supermarket shelves are estimated to contain genetically altered crops."⁴⁵ These crops are easier and cheaper to grow and can provide more food from less land. They need fewer chemi­cals in the way of insect repellants, herbicides, and fertilizers because they are "engineered to be toxic to insect pests or to be resistant to a popular weed killer."⁴⁶ For example, the insertion of Bacillus thuringiensis (B.t.) genes into corn enables it to resist the corn borer. Environmentally damaging herbicides can then be reduced. New strains of rice may also help solve the world famine problem. So-called golden rice can also help lessen vitamin A deficiency in poor countries because it contains greater amounts of the vitamin than other rice strains. Vitamin A deficiency causes blindness and other infections in much of the world's poorest children. "Edible vaccines in tomatoes and pota­toes" would make them more easily available to people than injectable ones.⁴⁷ Moreover, geneti­cally modified foods can also lead to "more health­ful foods, a cleaner environment, and a worldwide ability to produce more food on less land—using less water, fewer chemicals, and less money."⁴⁸ This is especially important for areas in the world— for example, some African countries—where fa­mine and malnutrition are serious problems. For example, opposition to genetically modified food has led to Uganda prohibiting efforts to develop a fungus-resistant banana, even though this fungus has seriously damaged its banana crop, one of its most important.⁴⁹

At the same time, protests have grown, espe­cially in Europe and Japan, but also in the United States. Some of the criticism is probably based on ungrounded fears. On the other hand, some haz­ards may be real. Herbicide-resistant crops may help create "superweeds." Neighboring crops may be contaminated with foreign genes. New forms of insects that are resistant to the inbred herbicides may develop. Crop antibiotic resistance may trans­fer to humans.⁵⁰ However, earlier worries about negative effects on monarch butterflies seem to have been alleviated.⁵¹ It is possible to reduce some of these risks, for example, by creating sterile plants—that is, plants that do not produce pollen, which could be a means of contamination. So far, many of the cited possible risks have not material­ized, but this does not prove they do not exist.

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