Researchers at Harvard University in the US have been granted permission to produce embryonic stem cell (ES cells) from cloned human embryos, two years after they first sought approval for the work. One research team, led by Doug Melton and Kevin Eggan, plans to ask women living in the Boston area to donate eggs for the research. The scientists want to use cloning technology to make ES cells genetically-matched to people with type 1 diabetes, Parkinson's disease and Alzheimer's disease. Another Harvard team, led by George Daley and Leonard Zon, want to use cloned embryos to study bone marrow and immune system disorders.
All the researchers are part of the Harvard Stem Cell Institute, which was established in 2004 to conduct ES stem cell research and analyse its ethical implications. In the US, most ES cell research has to be conducted using private funds, since President Bush restricted federally-funded researchers to working on ES cell lines created before 9 August 2001. Continuing pressure from many patients, doctors and scientists to change this policy means that ES cell research is set to become an important issue in this November's election campaigns.
Melton's team wants to take skin cells from patients and use those cells to create cloned embryos, from which they can derive stem cells that have the same genetic make-up as the patients. No other research group has yet achieved this feat, after work published by South Korean scientist Woo Suk Hwang was shown earlier this year to be faked. If successful, the Harvard team hopes to study the resulting 'diabetic' ES cells to find out when and why they start to develop abnormally, producing pancreas cells that stop making insulin - the blood sugar-controlling hormone that fails in people with diabetes. 'We can move studies from patients to the Petri dish', says Melton.
The scientists will ask healthy women to donate eggs specifically for the research, rather than use eggs left over after fertility treatment, since a plentiful supply of good quality eggs is a crucial factor in the success of the procedure. However, says Eggan, without payment, whether or not women will be willing to undergo the procedure 'we simply don't know and we'll have to wait and see'. Joseph Sanfilippo, president of the American Society for Reproductive Medicine, said that while some people will have concerns about the use of human eggs in the research, 'egg donation is done safely and ethically every day in infertility clinics around the country'. He added that 'Good informed consent procedures and careful screening of donors must occur for every donation, whether the eggs are to be used to help a family have a baby, or build towards better treatment of disease'.
The work is also controversial because it involves the destruction of early human embryos. 'You are making young humans simply to strip-mine them for their desired cells and parts', said the Reverend Tad Pacholczyk, of the US National Catholic Bioethics Center in Philadelphia, calling the Harvard research 'a fundamentally immoral project that cannot be made moral'. But Sean Tipton, president of the Coalition for the Advancement of Medical Research, said: 'We think that this research is very important, very promising, and we applaud Harvard for taking the initiative to move this work forward'.