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Scientists maintain that genetic modification of food crops is not new; humans have been tampering with nature for a very long time. Biotechnology critic Jeremy Rifkin disagrees.

Joseph Hotchkiss, Ph.D.

Professor of Food Science and Toxicology, Cornell University

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photo of Joseph Hotchkiss, Ph.D. I don't like the [phrase] "genetically modified food." Virtually all of our foods have been genetically modified. If you take the apple, for example, there are literally dozens of varieties of apples. How did we get those dozens of varieties? We genetically modified the apple through conventional breeding. We crossed one kind of apple with another apple, and we produced very different apples--different color, different flavor, different functions. What's different now is that we have some new technologies, some new techniques to do it.

Normal breeding can produce risks, just as any other genetic or other kinds of breeding can produce risks. ...

Celery naturally contains a photo-active toxicant, a chemical [that] becomes toxic when it hits sunlight. In California, a new variety of celery was bred that had--unknown to the people who bred it--high levels of this toxicant in it. ... The workers who harvested this [celery] came out with a very severe skin rash. Why? Because it had the high level of toxicant resulting from commercial, normal kind of breeding.

Norman Borlaug, Ph.D.

Distinguished Professor of International Agriculture, Texas A&M University
Remember also that Mother Nature has been making wide crosses across genera for millions of years. Ninety percent of the wheat produced today [and] used for bread is the result of a cross between three wild grasses that still exist in the foothills of Iran and Iraq and south Turkey. ... This was known long before agriculture was invented--millions of years ago--and it didn't transfer a gene. ... That was the grain of commerce from the early Sumerian period through the Greek into Roman times.

Martina McGloughlin, Ph.D.

Director, Biotechnology and Life Sciences Informatics Program, University of California-Davis

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photo of Martina McGloughlin, Ph.D. How old is biotechnology?

In the broader sense, biotechnology is literally thousands of years old. We've been modifying the world around us since we first realized we could make such things as cheese and bread and, very importantly, brew alcohol. ...

Comparing today's crops with their wild ancestors, what would we notice? ...

The ancestors of modern-day corn or potatoes are so totally unlike the present [cultivars] that for most people, they would be absolutely unrecognizable. There's also obviously a lot of negative aspects with respect to the ancestors of these plants, insofar as being able to supply sustenance. They are very small. They have poor yield. They oftentimes taste pretty awful. In many instances, they can be quite toxic. An example would be potatoes and tomatoes. They're all members of the deadly nightshade family. ... Over the many years of breeding, we've managed to breed out most of these toxins. ...

What's new about so-called genetically modified plants?

Over this century we've been introducing an awful lot of technologies in addition to the original selection and breeding. I think a lot of people don't realize this. We've been using mutagenesis breeding since the middle part of this century, and it's still done quite a lot. ... Several plants--in fact, something like 1,800 cultivars--have been introduced using this mutagenesis breeding approach. ...

Another type of technology that was introduced in the middle of this century is a technology called wide cross, or embryo rescue. In this instance, you're crossing two plants that are not sexually compatible, that is, species that would never interact in nature. Basically you're using scientific tricks to go in there and rescue that embryo that would normally be lost. ... There's a large number of products that come into the market each year, produced using these wide crosses. ...

Historically, genetic engineering was used for other applications, such as medicine, and in making enzymes, and it didn't attract much attention.

About 200 million people worldwide have benefited from the products of genetically engineered pharmaceuticals. Diseases that were really recalcitrant to treatment up until genetic engineering are now being treated very effectively. For example, one of them is human growth hormone, which is used to treat children that are suffering from human growth hormone deficiency. Prior to genetic engineering, this had to actually be extracted from the pituitary glands of corpses. Now using genetic engineering, you're just making a copy of the gene and you're actually making human growth hormone in large fermenters. It's easy to purify and it's highly effective, and it makes it much less expensive.

Likewise, diabetes has been treated using genetically engineered insulin. Prior to biotechnology, most insulin was produced using the pancreases of pigs. Of course, a lot of people were allergic to the product because it wasn't human. Now you make a copy of the human gene. You put it into your microbe of choice and grow it up again in fermenters.

Chymosin is another example. About 90 percent of all cheese is produced now using a genetically engineered enzyme. Prior to that, you had to isolate this enzyme from the forestomach of an unweaned calf. ... Using biotechnology, you make a copy of that gene from the calf, you put it into your microbe of choice, you grow it up in a fermenter. ...

Detergents have about three or four different genetically engineered enzymes, so that you can wash your clothes at room temperature. ... In addition, there are enzymes that protect the quality of your clothes. For example, there is a dye transfer enzyme that protects your clothes from transfer of dyes. ...

Jim Maryanski, Ph.D.

Biotechnology Coordinator, FDA

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photo of Jim Maryanski, Ph.D.Food has always been genetically modified?

Yes. I think we would consider all of the crops that we have as crops that have been subjected to some type of genetic modification. ...

From the early '80s, these methods were applied in medicine?

Yes. The first product that FDA reviewed was insulin produced through fermentation. That was approved in 1982. We even had experience prior to that, because [of a] scientist who had first raised questions about the safe use of this technology. That led to the development at the National Institutes of Health of guidelines for research. So when the questions started to be raised about the application of these techniques in the food sector, FDA had a lot of experience from the research guidelines through NIH [and] from its own experience in reviewing the first pharmaceuticals.

We've used genetic engineering in enzymes in foods, without public fuss.

Yes. The first food ingredient was something called chymosin, or what people may know better as rennet. It's the enzyme used to clot milk to make cheese. That enzyme was produced in a bacteria as the first product of modern biotechnology. FDA made a decision on [rennet] in 1990. We had a petition with an opportunity for public comment, and we received no comments from the public at all, at that time.

That was just the first of many enzymes?

Yes. There, of course, were other things--enzymes used to make high fructose corn syrup, for example, that's used in soft drinks.

Jeremy Rifkin

President, The Foundation on Economic Trends

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photo of Jeremy Rifkin Obviously, humans have been modifying nature genetically for 10,000 years with selection, breeding, mutagenesis. Why is this qualitatively different? ...

In classical breeding, genes are turned on and off when you cross strains. I have no problem whatsoever with classical breeding, because it's worked itself over 10,000 years and it's also part of the evolutionary schema. ...

What's different here is that we have now technologies that allow these life science companies to bypass classical breeding. That's what makes it both powerful and exciting. In classical breeding, you can cross close relatives. Taxonomy is an anthropocentric discipline anyway. You can, for example, cross various wheat strains and corn strains, etc. ... You can cross a donkey and a horse in classical breeding--they're very close relatives--and you can get a mule. But you can't cross a donkey and an apple tree in classical breeding.

What the public needs to understand is that these new technologies, especially recombinant DNA technology, allows scientists to bypass biological boundaries altogether. You can take a gene from any species--plant, animal, or human--and place it into the genetic code of your food crop or other genetically modified organism. [Crossing genetic information from one species to another] is something we've never seen in 10,000 years of classical breeding. ...

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