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BIOTECHNOLOGY. Biotechnology, in its broadest sense, is the use of biological systems to carry out technical processes. Food biotechnology uses genetic methods to enhance food properties and to improve production, and in particular uses direct (rather than random) strategies to modify genes that are responsible for traits such as a vegetable's nutritional content. Using modern biotechnology, scientists can move genes for valuable traits from one plant into another plant. This way, they can make a plant taste or look better, be more nutritious, protect itself from insects, produce more food, or survive and prosper in inhospitable environments, for example, by incorporating tolerance to increased soil salinity. Simply put, food biotechnology is the practice of directing genetic changes in organisms that produce food in order to make a better product.

In nature, plants produce their own chemical defenses to ward off disease and insects thereby reducing the need for insecticide sprays. Biotechnology is often used to enhance these defenses. Some improvements are crop specific. For example, potatoes with a higher starch content will absorb less oil when frying, and tomatoes with delayed ripening qualities will have improved taste and freshness.

Paving the Way to Modern Biotechnology

Advances in science over many years account for what we know and are able to accomplish with modern biotechnology and food production. A brief review of genetics and biochemistry is useful in evaluating the role of biotechnology in our food supply.

Proteins are composed of various combinations of amino acids. They are essential for life—both for an organism's structure, and for the metabolic reactions necessary for the organism to function. The number, kind, and order of amino acids in a specific protein determine its properties. Deoxyribonucleic acid (DNA), which is present in all the cells of all organisms, contains the information needed for cells to put amino acids in the correct order. In other words, DNA contains the genetic blueprint determining how cells in all living organisms store, duplicate, and pass information about protein structure from generation to generation.

In 1953 James Watson and Francis Crick published their discovery that the molecular structure of DNA is a double helix, for which they, along with Maurice H. F. Wilkins, won a Nobel Prize in 1962. Two strands of DNA are composed of pairs of chemicals—adenine (A) and thymine (T); and guanine (G) and cytosine (C). A segment of DNA that encodes enough information to make one protein is called a gene. It is the order of DNA's base pairs that determines specific genes that code for specific proteins, which determines individual traits.

By 1973 scientists had found ways to isolate individual genes, and by the 1980s, scientists could transfer single genes from one organism to another. This process, much like traditional crossbreeding, allows transferred traits to pass to future generations of the recipient organism.

One Goal, Two Approaches

The objective of plant biotechnology and traditional crop breeding is the same: to improve the characteristics of seed so that the resulting plants have new, desirable traits. The primary difference between the two techniques is how the objective is achieved. Plant breeders have used traditional tools such as hybridization and crossbreeding to improve the quality and yield of their crops with a resulting wide variability in our foods. These traditional techniques resulted in several benefits, such as greatly increased crop production and improved quality of food and feed crops, which has proven beneficial to growers and producers as well as consumers through a reduction of the cost of food for consumers. However, traditional plant breeding techniques do have some limits; only plants from the same or similar species can be interbred. Because of this, the sources for potential desirable traits are finite. In addition, the process of crossbreeding is very time-consuming, at times taking ten to twelve years to achieve the desired goal—and complications can arise because all genes of the two "parent" plants are combined together. This means that both the desirable and undesirable traits may be expressed in the new plant. It takes a significant amount of time to remove the unwanted traits by "back crossing" the new plant over many generations to achieve the desired traits. These biotech methods can preserve the unique genetic composition of some crops while allowing the addition or incorporation of specific genetic traits, such as resistance to disease. However, development of transgenic crop varieties still requires a significant investment of time and resources.

The Many Applications of Biotechnology

Since the earliest times, people have been using simple forms of biotechnology to improve their food supply, long before the discovery of the structure of DNA by Watson and Crick. For example, grapes and grains were modified through fermentation with microorganisms and used to make wine, beer, and leavened bread. Modern biotechnology, which uses the latest molecular biology technology, allows us to more directly modify our foods. Whereas traditional plant breeding mixes tens of thousands of genes, biotechnology allows for the transfer of a single gene, or a few select genes or traits. The most common uses thus far have been the introduction of traits that help farmers simplify crop production, reduce pesticide use in some crops, and increase profitability by reduction of crop losses to weeds, insect damage, or disease.

In general, the early applications of crop biotechnology have been at points in our food supply chain where economic benefit can be gained. The following are examples of modern biotechnology where success has been achieved or is in progress.

Insect resistance. Crop losses from insect pests can cause devastating financial loss for growers and starvation in developing countries. In the United States and Europe, thousands of tons of pesticides are used to control insects. Using modern biotechnology, scientists and farmers have removed the need for the use of some of these chemicals. Insect-protected plants are developed by introducing a gene into a plant that produces a specific protein from a naturally occurring soil organism. Bacillus thuringiensis (Bt) is one of many bacteria naturally present in soil. This bacterium is known to be lethal to certain classes of insects, and only those organisms. The Bt protein produced by the bacterium is the natural insecticide. Growing foods, such as Bt corn, can help eliminate the application of chemical pesticides and reduce the cost of bringing a crop to market. The introduction of insect-protected crops such as Bt cotton has allowed reduced use of chemical pesticides. This suggests that genetically engineered food crops can also be grown with reduced use of pesticides, a development that would be welcomed by the general public.

Herbicide tolerance. Every year, farmers must battle weeds that compete with their crops for water, nutrients, sunlight, and space. Weeds can also harbor insects and disease. Farmers routinely use two or more different chemicals on a crop to remove both grass and broadleaf weeds. In recent years new "broad-spectrum" chemicals have been discovered that control all these weeds and therefore require only one application of one chemical to the crop. To provide crops with a defense against these nonselective herbicides, genes have been added to plants that render the chemicals inactive—but only in the new, herbicide-resistant crop. Many benefits come from these crops, including better and more flexible weed control for farmers, increased use of conservation tillage (involving less working of the soil and thereby decreasing erosion), and promoting the use of herbicides that have a better environmental profile (that is, that are less toxic to nontarget organisms).

Disease resistance. Many viruses, fungi, and bacteria can cause plant diseases, resulting in crop damage and loss. Researchers have had great success in developing crops that are protected from certain types of plant viruses by introducing DNA from the virus into the plant. In essence, the plants are "vaccinated" against specific diseases. Because most plant viruses are spread by insects, farmers can use fewer insecticides and still have healthy crops and high yields.

Drought tolerance and salinity tolerance. As the world population grows and industrial demand for water supplies increases, the amount of water used to irrigate crops will become more expensive or unavailable. Creating plants that can withstand long periods of drought or high salt content in soil and groundwater will help overcome these limitations. Although genetically engineered crops with enhanced drought tolerance are not yet commercially available, significant research advances are pointing the way to creating these in the future.

Food applications. Research into applications of biotechnology to food production covers a broad range of possibilities. Examples of food applications also include increasing the nutrient content of foods where deficiencies are widespread in the population. For example, researchers have successfully increased the amount of iron and beta-carotene (the precursor to vitamin A in humans) in carrots and "golden rice"—a biotech rice developed by the Rockefeller Foundation that may help provide children in developing nations with the vitamin A they need to reduce the risk of vision problems or blindness.

Another example of food biotechnology is crops modified for higher monounsaturated fatty acid levels in the vegetable to make them more "heart-healthy." Efforts are also under way to slow the ripening of some crops, such as bananas, tomatoes, peppers, and tropical fruits, to allow time to ship them from farms to large cities while preserving taste and freshness.

Other possible food applications for which pioneering research is under way include grains and nuts where naturally occurring allergens have been reduced or eliminated. Potatoes with higher starch content also promise to have the added potential to reduce the fat content in fried potato products, such as french fries and potato chips. This is because the starch replaces water in the potatoes, causing less fat to be absorbed into the potato when it is fried.

Edible vaccines. Vaccines that are commonly used today are often costly to produce and require cold storage conditions when shipped from their point of manufacture in the developed world to points of use in the developing world. Research has shown that protein-based vaccines can be designed into edible plants so that simple eating of the material leads to oral immunization. This technology will allow local production of vaccines in developing countries, reduction of vaccine costs, and promotion of global immunization programs to prevent infectious diseases.

Global food needs. The world population has topped six billion people and is predicted to double by 2050. Ensuring an adequate food supply for this booming population is going to be a major challenge in the years to come. Biotechnology can play a critical role in helping to meet the growing need for high-quality food produced in more sustainable ways.

What Are Consumers Saying?

Crops modified by biotechnology (also known as genetically modified or GM crops) have been the subjects of public discussion in recent years. Considerable public discussion may be attributed to the public's interest in the safety and usefulness of new products. Although biotechnology has a strongly supported safety record, some groups and organizations abroad and in the United States have expressed a desire for stronger regulation of biotechnology-derived products than of similar foods derived from older technology. The assessment of the need for new regulation is related to an understanding of the science itself, as was detailed in the sections above; this is a continual process of development.

Consumer acceptance is critical to the success of biotechnology around the world. Attitudes toward biotechnology vary from country to country because of cultural and political differences, in addition to many other influences.

In the United States, the majority of consumers are supportive about the potential benefits biotechnology can bring. Generally, U.S. consumers feel they would like to learn more about the topic, and respond favorably when they are given accurate, science-based information on the subject of food biotechnology.

See also Agriculture since the Industrial Revolution; Agronomy; Crop Improvement; Ecology and Food; Environment; Food Politics: United States; Food Safety; Gene Expression, Nutrient Regulation of; Genetic Engineering; Genetics; Government Agencies; Green Revolution; High-Technology Farming; Inspection; Marketing of Food; Toxins, Unnatural, and Food Safety.

Charles J. Arntzen Susan Pitman Katherine Thrasher