First Endangered Species Cloned

by Cat Lazaroff

The scientific feat represents a couple of firsts: the first time an endangered animal has been successfully cloned, and the first time that a clone has been raised in the womb of another species.

The Massachusetts scientists responsible for BessieÕs unusual offspring say their accomplishment could herald a new era in endangered species preservation -- using clones to preserve genetic diversity.

The baby gaur, named Noah, is the only survivor of hundreds of attempts to produce a living gaur from the skin cells of a recently deceased male gaur.

Robert Lanza, vice president of medical and scientific development at Advanced Cell Technology (ACT), the company behind the cloning project, and a team of eight of his colleagues, fused 692 skin cells with cow eggs that had been emptied of their own genes. A similar technique was used in producing Dolly, the worldÕs first cloned sheep, three years ago.

The process resulted in 81 gaur embryos large enough to be implanted in the wombs of cows. Cows were used because the gaur is too endangered to be used in such experimental research.

Eight cows became pregnant. Five of those pregnancies ended in miscarriages, and two pregnancies were terminated so that the researchers could analyze the fetuses.

Noah is the sole survivor -- the sole copy of his dead "parent."

In a report in the current issue of the journal "Cloning," the ACT researchers say their success "would open the way for a new strategy on the part of conservation planners to help stem the loss of valuable biological diversity and to respond to the challenge of large scale extinctions ahead."

The new technology "also underscores the need to preserve and expand repositories of normal cell lines from species at risk of extinction," which could be used to enhance the genetic diversity of the species in the future.

Later this year, the researchers from Advanced Cell Technology (ACT) plan to try to clone an extinct species. The last known specimen of the Spanish mountain goat, or bucardo, was killed nine months ago after being struck on the head by a falling tree branch. Quick thinking biologists froze cells from the animal, which could be used to clone a living, breathing goat.

If ACT succeeds, they will have accomplished the almost unthinkable -- resurrecting a vanished species.

But because the scientists would have access to just one sex of the bucardo -- the last bucardo was a female -- no viable breeding pairs can be produced.

Still, Lanza said his company has a theory: if they can meld some bucardo cells with a male chromosome from a related goat, they may some day be able to clone male bucardos as well.

In the meantime, the ACT scientists are seeking permission to try to clone endangered giant pandas. They have asked the National Zoo, which lost its last panda in 1999, for access to frozen cells from Hsing-Hsing and Ling-Ling.

Zoo officials said in a statement that they have no plans at this time to provide those cells, but are "always open to new ideas that might advance the long term survival of endangered species."

If clones of dead pandas and other endangered species could be produced, it could preserve some of the genetic diversity of dwindling populations. Once an animals dies, the ACT scientists argue, its genetic material is lost.

In some cases, a handful of additional animals could prevent a "genetic bottleneck" -- a situation in which a species becomes so inbred that it can no longer produce viable offspring.

ACT has set up a nonprofit foundation for its species preservation work.