Scientists have cast serious doubts on whether the American biotechnology company that claimed a fortnight ago to have cloned a human embryo actually did so.
Scientists have cast serious doubts on whether the American biotechnology company that claimed a fortnight ago to have cloned a human embryo actually did so.
Advanced Cell Technology (ACT) of Massachusetts said in a scientific paper last month that it had cloned a human embryo – by the same method that British scientists used to create Dolly the sheep. The company said that a few cloned cells had multiplied a couple of times, putting them on the road to life, before dying.
But this week, Professor John Gearhart, a senior scientist in stem-cell research, resigned in protest from the editorial board of the online journal where the paper making the claim was published. He said: "I don't think they [ACT] have come anywhere near the mark of what it would take to prove that claim."
Other scientists have attacked the work as "half-baked" and "aimed at investors and the public, but not scientists".
Glenn McGee, a bio-ethicist who headed the company's ethics board, which advises on the moral aspects of experiments, resigned in protest last year. He did so after discovering that the company had started trying to clone animal and human embryos – an ethically prickly issue – without consultation. If the latest work was done without the approval of an ethics board, a shadow would be cast over its value.
The media spin that surrounded ACT's announcement in the last weekend of November has now come under scrutiny. The company's decision to publish in an online journal – e-biomed: The Journal of Regenerative Medicine – rather than either of the two biggest scientific journals, Nature or Science, is especially suspect. Such groundbreaking work might be expected to be published in the latter two. Nature and Science enforce a rigorous peer-review system, which also ensures that any potentially controversial work is approved by an ethics board.
ACT claimed that it had taken the nucleus out of a human egg, and inserted the DNA and nucleus from a "cumulus" cell (formed from a fertilised egg) into the "denucleated" egg. This, it said, then divided a few times before dying. That meant it could in theory produce a line of "embryonic stem cells", which are reckoned to have enormous potential medical value for treating all sorts of degenerative diseases.
But Professor Gearhart – who in 1998 was one of the first scientists to isolate and culture human stem cells – said on his resignation that ACT had only offered "very preliminary and unconvincing evidence" for its claims. He also said that the editor of e-biomed would not tell him which other scientists had "peer-reviewed" the work before publication – a standard method for verifying new work.
He argued that the paper failed to provide evidence that the DNA in the dividing fertilised eggs had actually come from the donor cell. If, instead, it was somehow the result of leftover DNA from the egg cell, the entire claim by ACT would be invalidated.
But that did not prevent the company garnering worldwide headlines when the news was released – on a Sunday, an unusual time of the week for a big scientific announcement.
"The [media] coverage was terrible," said Robert Foote, a pioneer in cloning and an emeritus professor at Cornell University. ACT, he said, has "good scientists working there, but what they did was half-baked."
Michael McKean, a professor at the University of Missouri School of Journalism, said the timing was perfect, though. "People were getting tired of the terrorist and war coverage." Arthur Caplan, of the Centre for Bio-ethics at the University of Pennsylvania, said the aim was to impress investors and the public, rather than scientists. ACT researchers have defended the work, and at a scientific gathering last week repeated their claims and spoke of more work – with monkeys – which, they say, backs them up.
The company, not listed on the stock market, has gained a high profile through its attempts to clone humans and endangered species. Last year, it said it had cloned an Asian gaur, an oxlike animal that is nearly extinct. That won a great deal of coverage. What did not was that the gaur calf died two days after its birth, of dysentery.
But both animal and human proved to be a source of friction with Dr McGee, who revealed in July this year that he had not been consulted on ACT's decision to go ahead with the work. He left the company last year and now says that too many corporate ethics boards in biotechnology companies are used as "rubber stamps" to make controversial research seem respectable.
Michael West, ACT's founder and chief executive, has reiterated that the company's ethics board was consulted about the animal and human embryo work.
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