In an email to the AP, the journal said one reason was the highly publicized 2004 fraud that came out of South Korea, where researchers claimed to have produced stem cells from a cloned human embryo.
The journal emphasized that its request did not indicate mistrust of scientists in the cloning field.
"Questions will likely be raised about the veracity of the (American) experiments, given recent history in the cloning field," the statement said. "We view this as a relatively straightforward way of putting these questions to rest."
The Australian study, by David Cram and others at the Monash University, used DNA analysis of the male macaque, the two monkeys that donated eggs for creating the embryos, and the stem cells.
The result "demonstrates beyond any doubt" that the stem cells came from cloned embryos, the Australians wrote in their verification paper in Nature.
Copyright 2007 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
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