Advertisement
 
(Page 2 of 2)

Cloned Goat Would Revive Extinct Line

Science: U.S.-Spanish project has sparked debate about how best to protect endangered animals.

December 24, 2000|AARON ZITNER | TIMES STAFF WRITER

To make a bucardo, Lanza and his colleagues will place a skin cell from Celia inside an egg from a domesticated goat or from an ibex, a close cousin of the bucardo. They expect the egg to use Celia's DNA to grow into a bucardo embryo, which they then will transfer to a surrogate mother--either a goat, an ibex or a goat-ibex hybrid.

Lanza acknowledged that cloning may leave the new animal with a small amount of DNA from the goat or ibex egg cell. Others have asked whether the bucardo will know how to act like a bucardo, given that it will have a mother from a different species.

"I think this will be a bucardo in any sense that you are concerned with," Lanza said. "It will have all the traits that we call bucardo traits."

The techniques used to clone the bucardo and gaur were developed for another purpose: to produce new drugs and medicines for people. Advanced Cell Technology, for example, wants to create cloned cows that produce a drug--human serum albumin--in their milk, which would help people with liver disease or severe burns. The company also is using cloning to create pigs with body parts suitable for transplantation into humans.

The bucardo--or capra pyrenaica pyrenaica--was populous in the Middle Ages, but it was severely pressured once guns became plentiful. By the turn of the century, big-game hunters would come from England and Germany to chase one of the rarest mammals in Europe.

Hunting and habitat pressures drove the bucardo into the most remote highlands of the Pyrenees, to "the worst terrain you can imagine. It lived in vertical cliffs," said Alberto Fernandez-Arias, who will be on the Spanish cloning team. He earned his doctorate by studying cross-species fertilization among the goat and ibex,

The Spanish government made efforts to save the bucardo, but it does not survive well in captivity. Efforts to mate it with other goat species failed. The last male died in 1991, leaving only three females.

By about 1996, Celia was alone. Fernandez-Arias won permission to take cells from her in May 1999 in the hope that someone would figure out how to clone her someday.

Park rangers found Celia dead in January under a fallen tree. Fernandez-Arias speculated that an avalanche, or high winds caused by an avalanche, knocked over the tree.

Another Task to Create a Second Sex

Although cloning an extinct animal would mark a new turn for biology, even more fantastic possibilities could be ahead.

One involves gender. Because Celia's cells could never produce a male bucardo, it will be impossible to use her to create a whole herd. But Lanza believes that he can replace one of her X chromosomes with a male Y chromosome from another species to create a male bucardo.

Dr. Kurt Benirschke, founding director of the Center for Reproduction of Endangered Species at the San Diego Zoo, who supplied the gaur cells to Lanza, said that creating a male of the species would be a "formidable" challenge. "But technology advances so fast that it is not impossible to dream about," he said.

Even more exotic is the prospect of reviving long-extinct animals, such as the woolly mammoth. Scientists have found one of the massive mammoths in the permafrost of Siberia. But the 20,000-year-old DNA in its cells is thought to be too damaged to produce a clone.

Still, Lanza speculates that science one day might overcome this hurdle. One possibility: Plugging any gaps in mammoth genes with DNA from the Asian elephant.

That fantasy, however, should not detract from the concrete benefits that cloning could bring to animal conservation today, according to Lanza and his supporters.

For example, said Benirschke, only a few thousand pygmy chimpanzees are left, including 130 in captivity. Their social structure demands that some males produce all the babies and others make none.

By cloning the males, scientists could pass a larger variety of genes to future generations, Benirschke said.

Mountain gorillas also might benefit, said Betsy L. Dresser, senior vice president for research at the Audubon Institute in New Orleans. The animals are being killed amid the Rwandan civil war in Africa, and only a few hundred remain.

"No matter how much money you pour in, you're not going to stop the war and save the gorilla," Dresser said. "There are no mountain gorillas in captivity anywhere. So unless somebody gets some genetic material from them, we're going to lose that species."

Advertisement
Los Angeles Times Articles
|
|
|