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Backgrounder on Genetic Modification of Crops and Animals

December 10, 1999

What is genetic modification?

Genetic modification, sometimes called genetic engineering, refers to the methods that make it possible to change the pattern in genetic material. That genetic material, found inside cells in molecules called DNA, is the "blueprint" for any living thing, whether it be plant, animal or the tiniest bacterium. Changing the pattern of the DNA molecules may make it possible to change countless characteristics in the living organism.

This ability to modify an organism's genetic makeup has innumerable uses for researchers trying to understand the basic biology of plants and animals, including humans. In applied plant science, the research is helping the development of agricultural crops that are better for the environment and for consumers. In applied animal studies, the work is leading to better health for pets, livestock and people.

What are the goals of genetic modification?

In crop production, the research aims to:

-- Reduce the need for chemical pesticides and herbicides

-- Reduce water use

-- Develop plants that are productive in marginal farmland, helping reduce world hunger

-- Increase nutritional quality

-- Improve flavor and appearance

-- Increase food safety

-- Improve plant qualities for harvesting, shipping and storage

-- Increase yields for farmers, reducing the need to farm fragile lands

-- Produce novel oils, plastics and pharmaceuticals

In animal studies, the research aims to:

-- Develop new vaccines, diagnostic tools and medicines for animals and people

-- Develop animal models for studies of human and animal disease

-- Increase the nutritional quality of meat, milk and other animal products

-- Increase yields of animal products

-- Reduce animal consumption by developing nonanimal sources for important oils and industrial enzymes

In both animal and plant studies, the research aims to identify possible risks posed by genetic modification to human or animal health or the environment.

How long has genetic modification been going on?

Nature is the master of genetic shuffling and is constantly sorting and resorting DNA, causing both subtle and profound changes in all living things. People first began their own DNA management thousands of years ago, when they began crossbreeding plants to produce better foods or fiber.

When did modern genetic modification begin?

In 1953, scientists discovered the structure of DNA, and in 1972, researchers developed a method for cutting and splicing DNA. That method became known as recombinant DNA, or rDNA, because it enabled scientists to cut and recombine segments of DNA. Since then, researchers have learned how to move genetic material in the form of DNA from one plant or animal to another. They can also take DNA from an animal and place it in a plant, and vice versa.

What are advantages of modern genetic modification over selective breeding?

Genetic modification is much more precise than selective breeding. By transferring only certain genes from one plant or animal to another, researchers can introduce one specific trait without also transferring dozens of unwanted traits, as often occurs in selective breeding. And genetic modification is the only existing tool available for producing certain vaccines, drugs and diagnostics.

What potential human health or environmental risks are posed by genetic modification, and what safeguards are in place at UC Davis?

As with most new technologies, genetic modification raises concerns, including the potential for creating undesirable effects in the food supplies of humans and wildlife and for creating herbicide resistance in weeds and pesticide resistance in insects. A number of campus research projects are aimed at identifying just such possible health or environmental risks.

Genetic modification research projects at UC Davis must comply with food and environmental safety regulations of the U.S. Food and Drug Administration and the U.S. Department of Agriculture. Additionally, research projects must be approved by the campus's biosafety committee.

How large is the research program at UC Davis ...

... in genetically modified crops?

UC Davis researchers are studying the application of genetic modification techniques in rice, corn, wheat, sugar beets, cotton, apples, walnuts and tomatoes. Researchers in six departments in the College of Agricultural and Environmental Sciences and the Division of Biological Sciences are involved. About 2,000 of UC Davis' 5,300 acres are devoted to agricultural research plots. A small proportion of those are planted in genetically modified crops.

Some of these research projects are aimed at improving flavor, shipping quality and disease resistance in tomatoes, shelf-life in apples, and insect resistance in walnuts.

... in genetically modified animals?

UC Davis researchers are studying the applications in mice, which account for 90 percent of the total number of animals involved, and in cows, pigs, sheep, goats and rats. Researchers in the College of Agricultural and Environmental Sciences, the Division of Biological Sciences and the School of Veterinary Medicine are involved in these programs.

The amount of animal research under way on campus will increase soon with the advent of a new collaboration with The Jackson Laboratory, the world leader in producing genetically customized laboratory mice. The new program, called JAX Research Systems at UC Davis, will provide the mice essential to the work of researchers at UC Davis and throughout the western United States. This work is of direct benefit to both human and animal health.

Some of these projects include genetically modifying viruses to produce vaccines for dogs, cats and livestock and to develop therapies to treat brain tumors in dogs. Other researchers are genetically modifying goats to improve the nutritional and processing qualities of milk. Some researchers are genetically modifying mice to serve as models for medical studies.

How long have UC Davis researchers been involved in genetic modification?

Like most agricultural research institutions, UC Davis scientists have been doing genetic modification research in plants and animals since the early 1980s.

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