Genetic Engineering: Future Foods : Part 3

by Food and Drug Administration (FDA)

(Page 3 of 3)

Public Acceptance

Whether genetically engineered foods succeed or fail ultimately depends on public acceptance. Early reports on the Flavr Savr tomato, the first recombinant DNA-derived whole food product to reach grocery shelves, were favorable. Calgene said sales in the product's first two markets — California and Illinois — were "a total success." Calgene chairman Roger Salquist said consumers responded "with purchases and praise."

In contrast, some consumer groups have criticized the Calgene product, demanding greater FDA scrutiny of genetically engineered foods or an outright ban on all of them. Their reasons range from safety fears to ethics. One group, the Environmental Defense Fund, said, "Consumption of some of these novel foods might present new hazards. [Some genetically engineered] compounds are new food ingredients and clearly should be evaluated for their safety."

FDA scientists and others in the field blame some negative consumer reaction on the recombinant DNA technique's complexity. The technology is difficult to understand, so there is a fear of the unknown. Genetic engineering "simply sounds scary," says Maryanski. "People call FDA and say, 'We don't want anyone tinkering with our food.' Then we remind them that there's hardly a food in the grocery store that hasn't been extensively tinkered with."

He illustrates this by comparing today's foods with those in the last century. "Take corn. Those nice, juicy ears of corn we have — they didn't exist. Some kinds of corn had a hard outer shell on the kernel that you couldn't eat until it was made into flour. And the kiwi was developed from a hard little berry. We only have our present-day kiwi — and our corn and wheat and hundreds of other foods — because of extensive plant breeding."

A New Tomato

The first genetically engineered whole product went on the market in May 1994 when FDA determined that a new tomato that can be shipped vine-ripened without rotting rapidly is as safe as other commercial tomatoes. The Flavr Savr is the first ready-to-eat food product available to the U.S. public that used recombinant DNA processes. Its maker, Calgene, Inc., created the Flavr Savr on the premise that many consumers are not satisfied with most store-bought tomatoes, especially in the off-season. Surveys show that though 85 percent of U.S. households buy fresh tomatoes, some 80 percent are displeased with the quality of grocery store tomatoes.

The problem is that tomatoes need warm climates to grow, so most off-season store tomatoes must travel a long way after they are picked. To survive their journey intact, tomatoes are picked while they are still green, which is a good way to avoid bruising, but which results in a tomato that is often described as having the consistency and mouth-feel of a tennis ball.

If picked when ripe, tomatoes rot quickly. Though Calgene vine-ripens its tomatoes, the company solved the rotting problem by inserting a reversed copy — an "antisense" gene of the gene that encodes the enzyme that results in tomato spoilage. This suppresses the enzyme that results in rotting, allowing the tomato to stay ripe, but not rot, up to 10 days — plenty of time for shipping and sale. Refrigeration is not necessary.

Though FDA policy didn't require premarket approval of the Flavr Savr tomato, Calgene sought FDA's review anyway. The company also asked FDA to approve as a new food additive the protein that produces kanamycin resistance. This marker protein allows breeders to identify early in the gene-transfer process which plant cells have successfully incorporated the new trait. Inserting the marker confers resistance to the antibiotic kanamycin. This is a valuable tool when trying to figure out which cells have the new gene and which do not. But it also adds very small amounts of a new protein to diets of millions of Americans and raises concerns about issues such as antibiotic resistance.

"That was one of the scientific issues we evaluated," says Jim Maryanski, Ph.D., FDA's food biotechnology coordinator. "And we found the kanr gene encoded marker protein would not affect the clinical effectiveness of kanamycin in people taking the drug orally."

FDA published regulations in 1994 allowing use of the kanr gene encoded marker protein in new plant varieties. Though not required, Calgene provided point-of-sale information that describes the tomato as a genetically engineered product. Reactions to the Flavr Savr have been largely positive, though some consumer groups have decried the product, giving it names like "Frankentomato." Others, including some restaurant chefs, issued public criticism of all recombinant DNA-derived foods.

But industry groups were enthusiastic. Carl Feldbaum, president of the Biotechnology Industry Organization, called the new tomato "a significant step forward for consumers in terms of the quality of the food they eat."

And Tom Stenzel, president of the United Fresh Fruit & Vegetable Association, said the genetically engineered food products now in development "will offer consumers more choices for improved quality, nutrition, and environmental benefits."

Ultimately, consumers will decide for themselves whether these new products and processes make sense. As for safety, FDA officials emphasize that these foods will be just as safe as products consumers are used to finding on their store shelves.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.