Scientists test limits on reinventing animals

March 31, 1993|By Liz Bowie | Liz Bowie,Staff Writer

For centuries man has played with nature, selectively breeding a cow to produce more milk or a flower to be more brilliant. And like Dr. Seuss, from whose imagination sprang Sneetchs, Lunks and Joats, scientists today are developing fantastic creatures, including salmon with chicken growth hormones and pigs with human blood.

Such experiments have limits. "We are certainly not going to be able to create Mr. Ed, the talking horse," said Lawrence Cunnick, president of Biocon Inc. of Rockville.

But animals of the future could grow faster, be immune to certain diseases or be used virtually as factories to produce drugs for humans.

Others, such as the swine being developed by New Jersey-based DNX Corp., would carry a gene that produces human proteins -- a quality that could allow their hearts, kidneys, lungs and livers to be transplanted into humans without fear of rejection.

The effort being made in the labs of universities and biotechnology companies has been speeded along recently by actions of the U.S. Patent and Trademark Office. After a five-year hiatus, the office has issued patents for five new animals since late December, providing a financial incentive for companies to manipulate the genetic code.

And with about 200 patent applications pending, the list of customized animals could grow rapidly.

Some biotech companies already use genetically engineered mice and rabbits in drug tests because they can get human diseases such as AIDS. They hope to extend such experiments to Alzheimer's and diabetes research, too.

But using so-called "transgenic" animals to produce drugs or other medical products is three to four years away.

Consider Herman the bull, now breeding in the Netherlands to create a new generation of Holstein cows.

He looks like any other bull. But when Herman was just an embryo in a test tube in 1990, a human milk gene was injected into him. Scientists hope some of his daughters will produce milk that contains an anti-bacterial agent commonly found in human breast milk.

California-based GenPharm International Inc. already has targeted potential customers. A purified form of that cow's milk could be incorporated in infant formula to make it more like breast milk. Or it could be given to AIDS patients, who have weakened immune systems.

Herman's first daughters should be born later this year, and their milk production will begin in early 1995. GenPharm hopes to begin selling the first product from Herman's progeny in 1996, says Chief Executive Jonathan MacQuitty.

The first U.S. patent for a transgenic animal, a mouse created by Harvard University researchers, was issued in 1988.

But that triggered intense criticism from animal rights activists, tTC ethicists and environmentalists. For years, the government did not issue any more patents, and dozens of applications piled up. Last December and February, patents on mice and a rabbit were issued.

The patent office denies that there was any self-imposed moratorium. "The prosecution [of the patent applications] was just taking that long," said a spokesman, Oscar Mastin.

However, some observers believe that outside criticism made the office wary of issuing more patents. As evidence that the office is shying from controversy, they cite the fact that it has not acted on patents for larger animals, such as pigs or cows.

Such patents are expected once again to bring a backlash -- and perhaps action from Congress or the White House. As a senator, Vice President Al Gore, for example, held hearings on whether constraints on the technology were needed.

Environmentalists and others argue that there are dangers in releasing transgenic animals into the environment, as well as ethical issues that haven't been fully explored.

"Can we allow ourselves to become architects of evolution?" asked attorney Andrew Kimbrell of the Washington-based Foundation on Economic Trends, a biotechnology watchdog group. "Is there an integrity and dignity to the animal kingdom?"

Putting one human gene into an animal may change it very little, he says. But what about inserting a combination of genes or making major changes to a creature? Should there be limits on that?

Even researchers believe that certain limits are important. For example, it might be unethical to produce farm animals with physical problems, they say.

And they generally would not want to mix the transgenic species with natural populations. While a transgenic Holstein might never meet a wild cow, there is the fear that a transgenic insect, salmon or striped bass could mate with the native species and eventually wipe it out.

Mr. Kimbrell and environmentalists agree. And they cite the dangers of an accidental release of laboratory animals, such as an AIDS-infected mouse that might breed with wild mice, or perhaps, begin the spread of a new strain of the virus.

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