A series of papers authored by a husband and wife who hold professorships in both Germany and the UK are being investigated for evidence of research misconduct.
The University of Lubeck in Germany is formally investigating claims of data duplication in six papers for which Ralf Paus is corresponding or senior author.
Professor Paus is professor of dermatology and experimental dermatology at Lubeck and spends 20 per cent of his time at the University of Manchester, where he is professor of cutaneous medicine.
Professor Paus confirmed to Times Higher Education that the allegations were being investigated by the German university, but said he was unable to comment further while the investigation was ongoing except to say that he expected it to show that there were "perfectly reasonable scientific reasons for these similarities" between the figures.
Last year a separate investigation by the Research Centre Borstel in Germany concluded that research misconduct had occurred in the lab of Professor Paus' wife, Silvia Bulfone-Paus. The case resulted in the retraction earlier this year of 12 of her papers, published between 1999 and 2009.
Professor Bulfone-Paus is a full professor at the University of Lubeck and director of the department of immunology and cell biology at the Research Centre Borstel.
She also spends 20 per cent of her time at the University of Manchester, where she is professor of immunobiology.
Professor Bulfone-Paus also features as an author on five of the six papers, which were published between 1997 and 2003, currently being investigated by Lubeck.
The earlier Borstel investigation blamed the data manipulation on two of her former postdoctoral researchers, Elena Bulanova and Vadim Budagian. But it also concluded that, as the pair's supervisor, Professor Bulfone-Paus bore "significant responsibility".
Following the investigation, her Borstel lab was downsized, she was denied any more students and was prevailed upon to resign as one of the directors of the centre.
In response to a public letter of support for her from 25 colleagues, the centre's board of directors criticised her "prolonged failure to be completely up-front about the nature and the extent of the misconduct occurring in her lab" and her "reluctance to take timely and appropriate action by herself".
The board also noted that, in the absence of any admissions of guilt, it "remains unresolved who carried out the manipulations". Neither of Professor Bulfone-Paus' former postdoctoral researchers are authors of the papers currently under investigation.
Both the original and the new allegations were made by Professor Bulfone-Paus' former colleague Karin Wiebauer, who is now a freelance molecular and computer biologist.
Dr Wiebauer told THE she had studied the latest papers to come under suspicion because she had "wanted to get an impression of the style of data presentations in Silvia Bulfone-Paus' articles in the time before Dr Bulanova joined her lab".
"That these articles have Ralf Paus as a common...author is, at least in this respect, purely accidental," she said.
The University of Manchester declined to comment on individual cases.
A spokesman said any allegations of misconduct were investigated under the university's code of misconduct.