South Korean scientists clone human embryo
Researchers in South Korea have created cloned human embryos to yield stem cells, touted as miracle material against many diseases.india Updated: Aug 12, 2004 13:37 IST
Researchers in South Korea have become the first to successfully clone a human embryo, and then cull from it master stem cells that many doctors consider key to one day creating customised cures for diabetes, Parkinson's and other diseases.
This is not cloning to make babies, but to create medicine. It's sure to revive international controversy over whether to ban all human cloning, as the Bush administration wants, or to allow this "therapeutic cloning" that might eventually let patients grow their own replacement tissue.
Embryonic stem cells are the body's building blocks, cells from which all other tissue types spring. They're present in an embryo only days after conception and are ethically sensitive because culling stem cells destroys the embryo.
Scientists have used therapeutic cloning to partially cure laboratory mice with an immune system disease. And they know how to cull stem cells from human embryos left over in fertility clinics. But attempts to clone human embryos — so the resulting stem cells would be genetically identical to the patient who needs them — have failed until now.
Scientists from Seoul National University say they succeeded largely because of using extremely fresh eggs donated by South Korean volunteers and gentler handling of the genetic material inside them.
The lead scientist, veterinary cloning specialist Woo Suk Hwang, will unveil the research at a meeting of the American Association for the Advancement of Science. Details will be published in the journal Science.
It's elegant work that provides long-anticipated proof that human therapeutic cloning is possible, said stem-cell researcher Dr Rudolf Jaenisch of the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts.
Still, "it's not of practical use at this point", Jaenisch cautioned.
Years of additional research are required before embryonic stem cell transplants could be considered in people, he stressed.
But it's sure to renew debate over whether all forms of human cloning should be banned. The US House of Representatives last year voted to do that, but the Senate was stalled over whether there should be an exception for some research.