Cute, Cuddly … Controversial

Ethical, safety issues arise as scientists try to bioengineer better food animals

Tom Abate / SF Chronicle 18feb01

A baby goat genetically engineered to produce milk with more protein sat on the lap of student Kira Farnhan at UC Davis. Chronicle photo by Lance Iversen

Student interns cuddled the three kids born just hours earlier at the veterinary lab of Jim Murray, an animal scientist at the University of California at Davis.

On the surface, the trio of young animals looked like any other newborn goats: awkward, spindly and cute.

But these kids didn't come into this world in the usual way. In September, when each was just a single fertilized cell, Murray used a fine glass needle to push a gene into each nucleus. The gene was supposed to increase the protein content of each goat's milk, which in turn would boost the cheese output at California dairies.

Murray's team then planted these gene-augmented embryos into surrogate nanny goats that gave birth last week to the latest controversy in biotechnology -- animals bioengineered to produce everything from more milk to leaner meat.

At a time when genetically engineered crops are stirring opposition, even the scientific backers of bioengineered animals are reluctant to push their creations into the market.

"To my knowledge, no transgenic animal has ever entered the food chain of the United States," Murray said.

In fact, what really worries scientists like Murray is that the controversy over biotech crops will stifle experiments to design animals that can better fill the meat and dairy appetites of a growing world population.

"Whether you like it or not, the past tells us that as people become more affluent, they tend to consume more meat," said Vernon Pursel, a biotech researcher at the U.S. Department of Agriculture in Beltsville, Md. "We're going to have to feed them on less (arable) space than we have now because the people are spreading out."

Critics say researchers with a vested interest overstate the need for bioengineered animals and overlook the risk that they might unwittingly create new health or environmental problems in the course of gene-splicing experiments.

"This is a technology in search of a need," said Margaret Mellon, a biotech critic with the Union of Concerned Scientists in Washington, D.C.

"You have scientists all around the world trying to get companies to take an interest in this technology" at a time when consumers are becoming leery of bioengineered crops.

At the moment, proponents and opponents of the technology are focused on the fate of a bioengineered salmon spawned with the help of a professor at the University of California at Berkeley.

In 1989, Berkeley's Boris Rubinsky was trying to figure out how fish survived in the Antarctic when he discovered that the fish had a promoter gene that pumped out extra doses of an antifreeze protein that was dormant in their bloodstream during warmer weather.

Rubinsky said the University of California patented his discovery and encouraged him to seek an industrial partner. The Berkeley professor eventually co-founded A/F Protein, a Canadian firm that put his promoter gene to a different use.

A/F spliced the promoter gene onto the salmon's growth hormone gene. The idea was to pump out growth hormone at a faster rate, which should allow the bioengineered salmon to grow to maturity more quickly than ordinary salmon.

Last year, A/F Protein asked the U.S. Food and Drug Administration for permission to put the faster-growing salmon on the market. "We have 10,000 fish swimming in a tank in Prince Edward Island," said Rubinsky. A/F would like to sell sterilized salmon eggs to aquaculture farmers, who would raise the fish for food.

FEARS OF 'FRANKENFISH'

Although Rubinsky said the company plans to sell only fish that can't reproduce, critics raised the specter that these "Frankenfish" would escape into the wild and outbreed native salmon. The FDA hasn't said when it will act or what it will do about the A/F Protein application.

Challenges to Rubinsky's technology continue on many fronts. Last week, for instance, the journal Nature published an article by Canadian scientists who suggested that the use of biotech stimulants to increase fish growth may yield fish with birth defects and other abnormalities.

Meanwhile, scientists meeting in San Francisco this week are debating why genetically engineered crops have become so controversial.

Kitty Smith, an economist with the U.S. Department of Agriculture, will speak today at a symposium organized by the American Association for the Advancement of Science. The event is being held at the Hilton San Francisco & Towers.

Smith suggested that experiments like Rubinsky's antifreeze salmon and Murray's milk-producing goats repeat the mistakes that caused opposition to the first generation of biotech grains.

The crops now on the market, Smith said, were bioengineered for greater disease resistance or faster growth -- improvements that benefited producers, not consumers.

"I don't see any market pull for animals that have characteristics that improve the ease of production," Smith said. "If animals were bioengineered for unique attributes that consumers perceived as valuable, like leaner, more healthful meats, there might be a demand for that."

Some animal bioengineers have already started to heed Smith's suggestion that they turn their attention away from production traits and toward what they hope will be a perceived benefit to consumers.

For instance, scientists at AviGenics Inc. in Athens, Ga., are in the early stages of trying to engineer disease resistance into chickens. Chickens today are raised in huge industrial operations that have a drawback -- diseases can spread quickly, decimating a flock.

To ward off infections, chickens are routinely fed antibiotics. In recent years, however, public health officials have become alarmed that the casual use of antibiotics is breeding bacteria resistant to current drugs.

FDA CURTAILS ANTIBIOTICS

Last year, the FDA began curtailing the use of some antibiotics in animal feed. AviGenics is working with Demegen Inc. of Pittsburgh to splice disease- fighting genes into chickens to fight conditions like salmonella.

"Our goal would be to create a chicken that requires less antibiotics," said AviGenics chief executive Carl Marharver. "What we're talking about is safer food products and poultry that have been administered fewer drugs. That's what consumers are saying they want these days."

Biotech critics are not impressed. Peter Rosset, executive director of Food First in Oakland, said initiatives like the AviGenics plan are only using biotechnology to cure the ills created by industrial farming operations in the first place.

Rosset would like to reverse the trend toward centralized agriculture, with its heavy reliance on biotech and chemical products, in favor of thousands of ecologically sound small farms.

"We need to conceive of other ways of rearing animals in integrated crop/livestock operations on a family scale," Rosset said. Properly run small farms would produce both crops and livestock more efficiently than giant corporate farms, he said.

Rosset's prescription would require an economic and social re-engineering that would reverse a decades-long decline in the farm population, as technology has increasingly replaced labor -- keeping a lid on food prices in the process.

One USDA economic report found that food expenditures, as a percentage of disposable income, fell from 13.8 percent in 1970 to 10.7 percent in 1997.

"Consumers in this country take our cheap, high-quality food for granted," said Matt Wheeler, a biologist at the University of Illinois at Urbana- Champaign. "And the way we're getting it is because of technology."

SELECTIVE BREEDING

Wheeler, who specializes in pigs, said bioengineering is simply the next step in a series of genetic alterations that began 9,000 years ago when humans began domesticating animals. Ever since, breeders have selected animals with desirable traits and cross-mated them to increase the prevalence of those traits.

Since the 1940s, the rise of artificial insemination technology has accelerated breeding trends, allowing agriculture scientists to create large herds quickly by using sperm harvested from prize males to inseminate thousands of females. In the hog kingdom, leanness has been one of the most desired traits.

"From the 1930s, breeding practices have taken hogs from 50 percent fat to 10 percent fat," Wheeler said.

The transformation of dairy cows through technology has been equally profound. UC Davis Professor Juan Medrano, an authority on milk production genes, said a national database tracks the milk output of cows sired by specific males in order to identify the best breeding stock.

In the dairy world, technology has also given cows a bigger role in improving the herd. UC Davis animal scientist Gary Anderson explained how embryo transfer allows prize cows to have many more offspring than they would naturally.

Scientists use hormones to stimulate egg production. Eggs are fertilized by the best available sperm. These well-bred embryos are implanted into surrogate cows.

"We breed the best 1 percent of cows to the best 1 percent of bulls," said Wheeler, the professor from Illinois. Over time, such practices have boosted milk output to the point where a single cow today produces as much milk as 2 1/2 cows did in 1940, he said.

Biotech scientists like UC Davis' Murray fear public concern over bioengineering may halt animal improvements beyond those made possible through artificial insemination or embryo transfer. His experiments take time. He won't know for a year, for instance, whether his gene insertion caused any increase in the milk protein content of his experimental goats.

"We're not there yet, but we can see a day when we could engineer out the gene that makes some people allergic to milk," he said. "But I'm afraid that we could lose this whole technology."

By the same token, biotech critics see gene splicing as an invisible line that animal scientists shouldn't cross.

"There are too many unanswered questions, too many largely unstudied potential health risks," said Rosset of Food First. "We'd want a whole gamut of risk assessment research to be funded and carried out before we started eating these animals."

E-mail Tom Abate at tabate@sfchronicle.com