The scientific journal, Nature, devotes quite a bit of its space in the January 12, 2006 issue to two editorials and one review article concerning ethics, peer review, and the spectacular failure of both in the publication of the "results" of the Korean veterinarian, Hwang Wu Suk, in the cloning of human embryos for the harvest of "patient specific" embryonic stem cells. Unfortunately, except for the table of contents, the on-line edition is subscription-only - but try to find a "dead tree" copy, if you can.
Here's the pertinent information on the report from the Seoul National University report that all of Hwang's reports in Science were completely false: Further investigation revealed that mitochondrial DNA from the cell line matched one of the egg donors, but the DNA inside the cells' nuclei varied at several locations. The committee concluded that the line was derived by parthenogenesis — where the single set of chromosomes in an egg develop as if it were fertilized. The images and data in the paper that showed perfect matches were fabricated.
The committee also found that Hwang worked with a staggering number of eggs — 2,061 from 129 women — despite claiming to have used only 242 eggs for the 2004 study and 185 for the 2005 study.
The findings are a huge setback for therapeutic cloning — the idea that cloned embryos could be used as a source of patient-matched stem cells to replace damaged tissues in a range of diseases. Even using numbers of human eggs of which other researchers can only dream, Hwang's team was unable to derive such stem cells, and the field is now left with no evidence that it is possible in humans at all (see Nature, 438, 1056–1059; 2005).
The committee did find that Hwang succeeded in cloning human embryos to the blastocyst stage, from which stem cells can be derived. But the success rate was just 10%, and they were "in poor condition". The only other group to have some success, Alison Murdoch's team at the University of Newcastle upon Tyne, UK, has cloned just a single blastocyst (M. Stojkovic et al. Reprod. BioMed. Online 11, 226–231; 2005).
Wednesday, January 11, 2006
Scientific Journal Rivalry?
Posted by LifeEthics.org at 9:55 PM
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment