WASHINGTON Cloning pioneer Ian Wilmut says he will no longer use in stem cell research the technique that resulted in the creation of Dolly the sheep but will instead pursue another form of experimentation that does not require the destruction of embryos.
Wilmut's announcement led some to speculate it might mark the "beginning of the end," as the British newspaper The Telegraph described it, for research, or therapeutic, cloning.
Wilmut, who had received a license two years ago in Great Britain to clone human embryos, said he has discontinued his experiments in the cloning field in order to work on a technique developed in Japan that he believes has more potential to produce stem cells that could treat debilitating diseases, The Telegraph reported Nov. 16.
The method Wilmut believes has a greater capability to result in therapies has been described as cell regression. The technique, pioneered by Shinya Yamanaka at Kyoto University, has been shown in experiments with mice to enable skin cells to be converted into cells with embryonic-like qualities, according to the newspaper. Such cells would have the advantage of not being rejected because they are the patient's own cells.
"The work which was described from Japan of using a technique to change cells from a patient directly into stem cells without making an embryo has got so much more potential," Wilmut said, according to BBC News. "Even though it's only been described for the mouse, when we were considering which option to pursue, whether to clone or whether to copy the work in Japan, we decided to copy the work in Japan."
The announcement of Wilmut's abandonment of cloning came a few days after it was reported that Oregon researchers had cloned embryos from primates for the first time in experiments with a 10-year-old rhesus macaque monkey. Scientists treated the report as a significant breakthrough, since it had been unclear if the cloning of primate embryos, including those of human beings, would be possible.
Wilmut's course change, however, might sound a death knell for research cloning, pro-life bioethics specialist Wesley Smith said.
"It seems to me that Wilmut would not have rejected his license unless he were convinced that cloning is just not going to work or be sufficiently efficient - given the human egg dearth - to be more than a novelty," Smith wrote on the weblog Bioethics.com.
"This is heartening news," Smith wrote. "Wilmut has no moral objection to human cloning. But perhaps he has looked into the tea leaves and made a pragmatic decision that bodes well for the human race."
Research, or therapeutic, cloning is performed with the goal of producing stem cells from human clones for experiments seeking therapies for a variety of diseases. The extraction of stem cells from the embryo, whether cloned or not, results in the death of the tiny human being. Pro-life advocates oppose embryonic stem cell research because of its destructive nature.
Cell regression, however, does not harm the donor.
Embryonic stem cells have been promoted for their ability to transition into other cell types, but they have yet to treat any diseases in human beings and have been plagued by the development of tumors in lab animals. Unlike research using embryos, extracting stem cells from non-embryonic sources - such as umbilical cord blood, placentas, fat and bone marrow - has nearly universal support. Such research has produced treatments for at least 73 ailments, according to Do No Harm, a coalition promoting ethics in research.
Wilmut believes the Japanese-based research could provide within five years a method that is both more rewarding and ethically acceptable.
A Scottish research team led by Wilmut announced in 1997 the successful cloning of a sheep, Dolly, which had been born the previous year. It was the first cloning of a mammal from an adult cell.
Wilmut is now a professor at the University of Edinburgh in Scotland.