The President's Council on Bioethics
1801 Pennsylvania Avenue, N.W., Suite 700
Washington, D.C. 20006
May 10, 2005
The President
The White House
Washington, D.C.
Dear Mr. President:
I am pleased to present to you Alternative Sources of
Human Pluripotent Stem Cells, a White Paper of the President's
Council on Bioethics.Since the publication of our report,
Monitoring Stem Cell Research, in January of 2004,
the Council has continued to ponder and discuss the ethical
challenges posed by human embryonic stem cell research and
the demands of scientists to develop new human embryonic stem
cell lines. While they may well in the future prove to be
of considerable scientific and therapeutic value, new human
embryonic stem cell lines cannot at present be obtained without
destroying human embryos. As a consequence, the worthy goals
of increasing scientific knowledge and developing therapies
for grave human illnesses come into conflict with the strongly
held belief of many Americans that human life, from its earliest
stages, deserves our protection and respect.
Seeking to advance biomedical science while upholding ethical
norms, the Council has taken a keen interest in recent suggestions
that science itself might provide a way around this ethical
dilemma. Accordingly, we have been looking into ways of obtaining
pluripotent, genetically stable, and long-lived human stem
cells (the functional equivalent of human embryonic stem cells)
that do not involve creating, destroying, or harming
human embryos. We have found that there are, broadly speaking,
four such possible approaches: stem cells might be obtainable
from dead embryos; from living embryos, by non-destructive
biopsy; from bioengineered embryo-like artifacts; and from
reprogrammed adult somatic cells. In this White Paper, we
introduce each of these four approaches and offer a preliminary
analysis of their strengths and weaknesses, ethical, scientific,
and practical.
While different members of the Council assess the merits
of the four proposals differently, the Council shares the
view that the group of proposals here discussed-and others
like them that they may stimulate-deserve the nation's careful
and serious consideration. We offer this White Paper both
to enrich and inform public discussion of the ethical dimensions
of stem cell research and especially to encourage scientists
to explore these and other possible ways to press forward
with pluripotent stem cell research in ways that all Americans
can wholeheart-edly support.
Mr. President, allow me to join my Council colleagues and
our fine staff in thanking you for this opportunity to offer
you and the American people our assistance in the critical
efforts to promote a biomedical science that will simultaneously
serve human needs and preserve human dignity.
Sincerely,
Leon R. Kass, M.D.
