The prohibition was challenged in 1999 by the Clinton administration, which wrote new NIH guidelines permitting embryonic stem-cell research by federal agencies - provided stem cells were extracted with private funds.
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"The key here is a lot of people say, 'Well, you are against all stem-cell research.' That is not true. … What the media do not cover enough of are the success stories of the alternative research and some of the negatives which have been associated with the embryonic stem-cell research," says David Prentice, a professor of life sciences at Indiana State University and an adjunct professor of medical and molecular genetics at the University of Indiana School of Medicine.
Writing in the prestigious medical journal The Lancet, Neil Scolding of the Institute of Clinical Neurosciences at the University of Bristol in England argued that "the rapid progress made in research with stem cells from adults and the clear evidence of the potential therapeutic value of these stem cells make it misleading to suggest that arguing against legalizing embryo research is to deny sufferers hope, or to prevent scientific or therapeutic progress."
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a study conducted by California-based Geron seeking to produce brain cells from embryonic stem cells not only failed to do so, but actually killed brain cells.
Almost all the positive accomplishments in stem cell use have been made with adult stem cells. In cases where the cells can be harvested from the patient who later receives them, adult stem cells don't threaten the recipient's immune system.
If federal funds are not diverted to embryonic stem cell research, adult stem cell therapeutics will become a reality much sooner.