1. Home>
2. Specialties>
3. General Medicine>
4. Summary and Comment

Therapeutic Human Cloning Reported

A Korean group has harvested ES cells from a human blastocyst: Is this the first step toward alleviating degenerative diseases?

The editors of Science have retracted publication of the article on which this review is based.

Dolly, the cloned sheep, showed that the nucleus of an adult cell could be used to clone a mammal (Journal Watch Mar 14 1997). Two years later, the first human embryonic stem (ES) cells were isolated.

Together, these advances suggested that a human patient with a degenerative disease could be treated with his or her own stem cells someday. First, a clone would be created using a nucleus from one of the patient's own cells. A blastocyst would form, and ES cells would be harvested from the blastocyst. Because ES cells reproduce indefinitely, many genetically identical ES cells could be collected and transplanted without fear of immunologic rejection. However, attempts to achieve these steps in monkeys have been repeatedly unsuccessful.

Now, a Korean team has reported that it has succeeded in creating a human clone and in harvesting ES cells from the blastocyst. Although the results are not definitive, most experts believe that this group has succeeded in obtaining clone-derived ES cells.

Comment: This landmark report reveals that it is feasible to create a very early human clone and to harvest functional stem cells from it. For those who are ethically opposed to such "therapeutic cloning," the report will be a call to action. For those who think therapeutic cloning is ethical and that it might help to alleviate many degenerative diseases, this report will generate calls for the U.S. president and Congress to loosen current U.S. restrictions on research.

— Anthony L. Komaroff, MD

Published in Journal Watch General Medicine March 9, 2004

Citation(s):

Hwang WS et al. Evidence of a pluripotent human embryonic stem cell line derived from a cloned blastocyst. Science Express 2004 Feb 12 . (http://www.sciencemag.org/cgi/rapidpdf/1094515v1.pdf)

Vogel G. Scientists take step toward therapeutic cloning. Science 2004 Feb 13; 303:937-9.

• Original article (Subscription may be required)
• Medline abstract (Free)

Kennedy D. Editorial retraction. Science 2006 Jan 20; 311:335.