A research article that made headlines around the world had an introduction that was heavily plagiarised.
The report on the creation of sperm from human embryonic stem cells had a 728-word introduction, nearly 70 per cent of which was lifted word-for-word from a 2007 paper not listed in its references.
The report, from a prominent research team at Newcastle University, has been retracted. The Stem Cells and Development journal, home of the original submission, has declined to republish an amended version, a move that leaves the science - which some questioned at the time - in limbo.
As Times Higher Education reported online, the paper, "In Vitro Derivation of Human Sperm from Embryonic Stem Cells", was retracted by the journal on 28 July.
Graham Parker, its editor-in-chief, was alerted by another journal, Biology of Reproduction, that much of the introduction was copied from an earlier paper, "In Vitro Gamete Derivation from Pluripotent Stem Cells: Progress and Perspective", by Makoto Nagano, a Canadian-based researcher.
The sperm-creation paper, which had been peer-reviewed and accepted for publication but had yet to undergo copy-editing, was published online on 7 July, generating widespread media coverage.
It lists Karim Nayernia, professor of stem-cell biology at the North East England Stem Cell Institute and the Institute of Human Genetics at Newcastle University, as the corresponding author. It has a total of 13 authors, eight of whom are part of the Newcastle team.
Newcastle said the text in the introduction was from an "old version of the paper that was submitted in error" and was "copied without attribution" by a research associate who has since left the university.
But while a corrected version of the manuscript has now been submitted, Dr Parker said he would not republish it because the explanation that it was an inadvertent mistake "had not been substantiated".
"I had hoped my investigation of the author's explanation for the plagiarism could be substantiated. It was not, therefore I could not proceed," he said.
Newcastle said the paper would now be submitted to another journal, but several leading scientists have criticised the senior researchers behind the paper.
"The buck stops with the corresponding author," said Allan Pacey, senior lecturer in andrology at the University of Sheffield. "People use postdocs all the time to draft stuff and that is fine ... but at some level the person in change has got to take responsibility," he added.
Robin Lovell-Badge, head of the division of stem-cell biology and developmental genetics at the Medical Research Council National Institute for Medical Research, added: "Often the first author, a postdoc or student, would provide a first draft, but this does not absolve the other authors from any responsibility they have to check the paper, especially if they want their names associated with something that they knew was going to be contentious."
Newcastle said in a statement that the science behind the research and its conclusions were not in question. It added that it would be "further examining the supervision of research associates in the process of submission to an academic journal".
The university declined a request to interview Professor Nayernia.