Embryonic stem cells come from blastocysts, human embryos a few days after fertilisation. In order to use them for study, stem cells must be removed from inside the blastocysts, thereby destroying the embryos. Under proper conditions, the removed cells are able to replicate themselves indefinitely and can be made to develop into any kind of tissue.
Many scientists believe that these cells offer an incredible potential to discover cures for some of today's worst diseases such as Parkinson, Alzheimer, diabetes or even cancer.
Opponents to the research claim that, however noble the goal, it does not justify the means, and that the destruction of embryos, the equivalent of killing a human being, can never be justified. They also suggest that scientists should focus on adult stem cell research since, while less promising than embryonic stem cell research, it does not carry this moral problem.
President Bush, a fierce anti-abortionist, thus faced an agonizing dilemma: can we allow ourselves to saves lives if, to do so, we must destroy human embryos? And should we be doing all this with the taxpayers' money?
Mr Bush's decision consisted of authorizing federal funding for research on existing stem cell lines from embryos that had already been destroyed. About sixty such lines exist in various research facilities around the world. Funding would not be available, however, for research on stem cells removed from the tens of thousands frozen embryos stored in fertility clinics across the country, nor would it be available for research on any new sources of stem cells, including those comming from embryos created specifically for research purposes or from cloned embryos, which are illegal in the United States. The amount of federal funding available to researchers should be around $250 million for the current year.
In addition, Mr Bush announced that he was creating a President's Council on Bioethics to "monitor stem-cell research, to recommend appropriate guidelines and regulations and to consider all of the medical and ethical ramifications of bio-medical innovation". It will be chaired by Dr. Leon Kass, a conservative biomedical ethicist from the University of Chicago.
After learning of his decision, none of the two sides in this debate seemed pleased with the half-apple they received.
Most conservative opponents and anti-abortionists condemned the decision by accusing him of supporting an immoral research project. "He knows those cells were obtained by killing a person, and that makes him complicit in an illicit action" said Father Joseph Howard, executive director of the American Bioethics Advisory Commission. Some groups, however, supported the President's choice, such as the National Right to Life Committee, saying that it "prevents the federal government from becoming a party to any further killing of human embryos for medical experimentation".
Reaction from the scientific community as so far been mixed. While researchers expressed relief that funding was not completely prohibited, they also shared concerns over the severe restrictions of federal funding, particularly on the restriction of research to the existing stem cells lines. Many scientists hoped to have access to the regularly destroyed excess embryos at fertility clinics. "It's ideology first, science in the back seat," commented Dr. Steve Miles, a professor of medicine at the University of Minnesota's Center for Bioethics.
About sixty percent of Americans support federal funding for stem cell research.
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