The British brain drain may be about to be reversed in human stem-cell research.
Several American scientists are believed to be pursuing moves to the United Kingdom to take advantage of supportive legislation and improved funding as well as the opportunity to work alongside some of the field's British pioneers.
Excitement has grown in the science community in recent years as the prospect of new therapies to repair defective tissues by controlling stem cells has increased.
Although it will be six months before the House of Lords' stem cell research select committee reports its findings, the promise of a medical revolution has given the field broad parliamentary support.
Funding for biomedical research in general has been boosted. A project team set up by the research councils met in May to discuss a national stem-cell bank for British scientists.
This climate contrasts with the uncertainty in the United States. There, ethical doubts have denied federal funding for research involving human embryos, which sparked protests, petitions and lawsuits from scientists.
Some US researchers have turned to industry and charities for funds, but others are now considering moving abroad.
Robin Lovell-Badge, head of developmental genetics at the National Institute of Medical Research in London, said: "It is early days, but I think this will definitely happen."
He said he had talked with one US scientist - "a well-known, senior person in the field" - who would move to the UK "if he gets a reasonable deal".
Janet Rossant, a former Oxford University stem-cell researcher in mice, now professor of molecular and medical genetics at Toronto University, said: "I know one (scientist) who is looking to move to the UK for a variety of reasons, including the environment for stem-cell research."
Professor Rossant said it was unclear if there would be a mass exodus of US scientists. However, she believed improved funding for science in the UK would tempt more leading scientists to immigrate.
Richard Gardner, Henry Dale research professor at Oxford University, said recruitment of US stem-cell researchers was discussed at the Wellcome Trust this year.
However, he felt the persisting uncertainty meant "people are not rushing to move here".