Unbalancing Act

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Does our food supply need a bio break?

Can bioengineered or genetically modified (GM) food help alleviate food shortages, preserve the natural environment, and keep us healthy? Maybe.

Through changing the genetic structure of a plant, scientists can design plants to maximize their good traits and discard their bad ones. Corn, for example, can be changed to require less water or to resist particular insects. Less reliance on irrigation and less use of chemical insecticides could mean less disruption to the environment. Likewise, rice can be modified to provide more nutrients and vitamins. One new kind of rice, called "golden rice," has additional folic acid and vitamin A. Eating this rice may prevent birth defects and blindness or even death caused by a vitamin A deficiency. Around the world right now, between 124 million and 250 million pre-school children suffer from vitamin A deficiency.

The basic idea of genetic modification is not new. Through selective breeding, farmers have been changing crops for thousands of years. Just about all the fruits and vegetables you see in the grocery store come from changes human beings have made to plants in their "natural" state. Many varieties of apples, for example, come from crossbreeding different types.


Before bioengineering, 20 years of breeding produced this disease and cold resistant orange. Source: USDA Before bioengineering, 20 years of breeding produced this diseaseand cold resistant orange.
Source: USDA

But bioengineering takes this concept much further: It changes plants by adding genes from unrelated species. That's why these plants are also called transgenic—they contain genes from species with which they do not normally reproduce.

How does it work?

  • Let's say, for example, that you wanted to make a tomato that resists frost. To do this, scientists would crossbreed the tomato with a gene from a fish called the arctic flounder. With a tomato that would not be damaged or die if cold weather hits, farmers would have larger crops—and more tomatoes would make it to our tables.

  • The same techniques could be used to deliver medicines. Bananas, for example, could be genetically modified to deliver hepatitis B vaccine. Why do this? Cost of the vaccine is now $100-$200 per person, much too expensive for people in most developing countries. A banana that delivers the same vaccine would cost pennies per person. Experts estimate that growing 10 hectares (24 acres) of vaccine-fortified bananas could immunize every child in Mexico under 5 years old-saving thousands of lives. Also, eating a banana also would be much less scary than getting a shot.


Changing the genetic structure of wheat can make it more disease-resistant. Source: USDA Changing the genetic structure of wheat can make it more disease-resistant
Source: USDA

This may sound like science fiction, but it's not. Researchers are doing this work right now. In fact, more than 130 million acres of transgenic crops have been planted around the world, with nearly a 20 percent increase in the year 2001 alone.

You might find the idea of GM food exciting and a little scary at the same time. It raises three general concerns:

  • Will the changes do long-term harm to human health? Bioengineering "improves" plants by doing something nature never does-adding genes from other species of plants and even animals. Although all tests up until now indicate that this causes no problems, no one can know for sure.

  • What will happen if the genetically modified crops escape? If wind carries pollen from GM corn into a field of "regular" corn, will they breed and take over? The result may be yet another kind of plant, and it may be harmful one.

  • Will GM crops produce profits only for the large corporations that "invent" them, or will they become available to farmers in developing countries-where most of the world's hungry people live?

No one yet knows the answers to these questions. But we will need answers soon because there are lots of hungry people and because technology can be difficult to "stop."

In the meantime, many countries—particularly in Europe—are banning genetically modified food items unless they are clearly labeled so that people can decide for themselves if they want to eat them.