Tetra, The Cloned Monkey

The world's first monkey cloned by embryo splitting is contributing to the growing debate about the ethics of cloning.

CBS News Correspondent Elizabeth Kaledin reports.

"Tetra is the world's first monkey cloned by embryo splitting," says Gerald Shatten of the Oregon Regional Primate Research Center.

Embryo splitting involves dividing an eight-cell embryo into four identical parts. It's been done before in mice and cows but this is the first time a monkey, the closest genetic relative to humans, has been cloned.

Scientists believe identical monkeys will be the best models for studying human diseases.

"The potential to understand the genetic basis for disease in a close animal relative may lead to life-saving cures faster," says Shatten.

It's completely different from the cloning of Dolly the sheep that involved a procedure called nuclear transfer. But both experiments have something in common: their contribution to a growing debate about the ethics of cloning.

Embryo splitting basically duplicates in the lab what the body does naturally in creating identical twins, triplets and quadruplets. For that reason, there's fear the technology may be rushed in to answer problems of human infertility and open the door to the possibility of human clones.

"There's always been a discussion about using this technology for increasing the number of embryos for couples in infertility treatments. To my knowledge it hasn't been demonstrated yet in humans but there's clearly that potential there," says Dr. John Gearhart of Johns Hopkins University.

There are other concerns about simply creating animals for the sole purpose of experimentation and research.

"Monkeys are just much more sympathetic creatures than lab mice or rats," says Tom Murray of the Hastings Center.

It's unclear what direction Tetra the monkey will take the future of cloning but the warning among those debating its merits is: Proceed with caution.