International journal Nature has found no sign of fraud in a 2009 paper published by Professor Konrad Hochedlinger and colleagues. The allegations came from a group calling itself 'Stem Cell Watch' which has made a series of accusations of fraud against a number of leading stem cell scientists, including Professor Hochedlinger, citing repetition and the manipulation of images among its reasons for concern.
The group, whose membership remains unknown, said: 'We are continuing to point out suspicious results and duplications reported by scientists in the stem-cell field'. Nature News reports the group claims to comprise of biology students who get together to discuss papers come across in their studies. The group claimed the images in Professor Konrad Hochedlinger's paper 'looked weird' and had been subjected to digital enhancement but a subsequent investigation by Nature found no evidence to support such claims. 'The image has been evaluated by professionals and we are satisfied they are original and not unduly manipulated', the publication said in a statement.
Commenting on the accusation, Professor Hochedlinger, who submitted the originals of the images in question to Nature, said: 'I have never received e-mails like this before and, to be honest, I find it quite upsetting'. The accusations, which were made anonymously, have caused upset in the scientific community and researchers have said such allegations should have been made in an open and transparent manner. 'I find this kind of activity unhelpful and defamatory', said Dr Douglas Melton, co-director of the Harvard Stem Cell Institute in Massachusetts.
Explaining the decision to investigate, Nature said: 'While we wouldn't encourage anonymous accusations, least of all those broadcast indiscriminately, there have been occasions where anonymous whistle-blowing has revealed fraudulent papers, so we will at least consider such accusations'.
Professor Robin Lovell-Badge at the National Institute for Medical Research, London, said he finds the incident worrying. 'Although we don't want fraudulent work to be published', he said, 'this group does not seem to have the skill or knowledge to make a fair assessment'. The International Cellular Medicine Society, which also operates a website also called 'Stem Cell Watch', has no association with the group that made the allegations.