In an Editorial in today’s Nature (450, 457-458; 2007), Replicator review, the journal describes its publication of “what we expect to be the final word on whether nuclear transfer can work in a primate — ”https://www.nature.com/nature/journal/v450/n7169/full/nature06357.html">a paper by J. A. Byrne et al. showing not only that it is possible to clone primate embryos by somatic-cell nuclear transfer but also that precious embryonic stem cells can be derived from the embryos. If embryonic stem cells live up to their promise, the technology could be used to derive patient-tailored stem cells."

The Editorial goes on to describe how Nature took the unusual step of soliciting an independent verification of the paper during the process of peer review. “This is the first time that Nature has obtained second-party replication ahead of publication. It should not be seen as reflecting a mistrust of scientists in the cloning field or scepticism about this particular research group. Rather, our actions fulfilled ”https://www.nature.com/nature/journal/v439/n7074/full/439243a.html">a statement in an Editorial from 2006 that was conceived in the aftermath of the Hwang affair: “Keeping in mind the principle that extraordinary claims require extraordinary proof, Nature may in rare cases demand it.”

Nature will continue to evaluate the need for such validation on a case-by-case basis. Meanwhile, researchers should consider maintaining tissue samples, and trying to establish and fulfil requirements that may go beyond the routine, as Byrne et al. did for their cloning paper. In that way, remarkable scientific developments can remain as free as possible from unwarranted speculation and controversy."

Also in this issue of the journal is a News and Views article on the new work, by Ian Wilmut and Jane Taylor (Nature 450, 485-486; 2007); a News story featuring an interview with one of the authors of the paper; and a Nature editors’ one-paragraph summary of the work.

A blog discussion of peer-review challenges in stem-cell research and the peer-reviewers’ reports for the paper by Byrne et al. can be found at Nature Reports Stem Cells.