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FAQs about Cloning, Stem Cell
Research, and ASRM's Position
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What is Somatic Cell Nuclear Transfer (SCNT) and Therapeutic Cloning for Stem Cells?
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What are stem cells and what research is being done on them?
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If cloning research is allowed, isn't ASRM mandating the destruction of embryos?
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Where will the eggs used come from, and won't egg donors be exploited?
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How many embryos are in freezers already? And are those embryos available for stem cell research?
1. What is Somatic Cell Nuclear Transfer (SCNT) and Therapeutic Cloning for Stem Cells?
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This process involves the nucleus of an egg cell, replacing it with the material from the nucleus of a "somatic cell" (a skin, heart, nerve or any other non-germ cell), and stimulating this cell to begin dividing.
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This egg cell is never fertilized by sperm, and the genetic material within the cell is virtually identical to the genetic material extracted from the skin or other cell.
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Once the cells begin dividing the stem cells can be extracted 5-6 days later.
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By using SCNT, scientists hope to understand how the protein factors in the egg cell cause these already specialized somatic cells to become stem cells. Once we learn how this cell "de-differentiation" occurs, we will no longer need to use egg cells.
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Because of SCNT, science could advance to a point where millions of people will have access to life saving therapies developed using their own DNA.
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When cells, including donated organs, tissues, or blood, are transplanted or transfused, the recipient's body mounts a rejection response, attacking these cells as foreign. SCNT could allow an individual's own cells to be used to treat or cure that person's disease, without risk of introducing foreign cells that may be rejected.
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Other methods of developing and harvesting stem cells may be developed and utilized in the future.
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Somatic cell nuclear transfer research is an important subset of stem cell research and could allow researchers to develop stem cell therapies that are specifically tailored to an individual's medical condition and that do not trigger an immune rejection response.
2. What are stem cells and what research is being done on them?
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Stem cells are special cells found in very early stage embryos (i.e., 5 days after fertilization of an egg) and in some types of adult tissue.
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Stem cells are "undifferentiated" cells (sometimes referred to as "pluripotent"), which means:
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they have not yet developed into a particular type of cell that performs a specialized function (e.g., skin, heart, or nerve cells); and
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they can, under circumstances, develop into many different types of cells.
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Stem cell research promises to allow these undifferentiated stem cells to be stimulated to develop into various types of specialized cells or tissue.
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The molecular processes discovered in working with stem cells derived from SCNT will be extremely valuable in finding ways to increase the utility and versatility of adult stem cells.
3. Which legislative bill is ASRM endorsing?
From ASRM's point of view, all legislative bills currently being discussed could be improved a little. Currently ASRM feels it is more important to talk about what should and should not be in a bill.
4. If cloning research is allowed, isn't ASRM mandating the destruction of embryos?
That's not the way ASRM sees it. While human embryos at any stage are worthy of special respect and consideration, most of them will never be capable of giving rise to a baby. It is not at all clear that SCNT could ever be used to produce a viable human embryo capable of developing into a normal human being. We think SCNT can produce some very special cells, but not yet a child.
5. Is ASRM for stem cell and other kinds of embryo research?
YES. ASRM thinks the best way to oversee this research and the fastest way to develop the science is to bring it under federal control via NIH funding.
6. What about adult stem cells? Aren't they just as good?
It is important that research into possible uses of adult stem cells continue. But right now it does not appear they will be as useful as embryonic stem cells.
7. Where will the eggs used come from, and won't egg donors be exploited?
Egg donation is already a vital therapy for some infertile couples. The ASRM and SART have in place strong guidelines on how to screen, counsel, and compensate potential egg donors. All these guidelines could be used if seeking donors for stem cell or SCNT purposes as well as for reproduction. The ASRM is already working with the FDA to develop regulations on donated reproductive tissues. These would apply whether these tissues are to be used for reproductive purposes or for stem cells.
8. How many embryos are in freezers already? And are those embryos available for stem cell research?
According to a study
performed by ASRM's affiliate SART- the Society for Assisted Reproductive
Technology and the RAND published in the May 2003 issue of Fertility
and Sterility, there are nearly 400,000 embryos stored in
cryopreservation facilities across the country.
Although this
is a high number, the overwhelming majority of these embryos (88.2%) are
being held to help patients have children in the future. About 4% of
cryopreserved embryos are available for donation. Slightly more than half
of those (about 11,000) are designated for research, while about 9,000 are
slated for donation to help other infertile couples have children. We do
not know how many of the embryos to be donated for research will go to
stem cell research and how many will go to other types of embryo research
projects.
9. If cloning can be done safely, will ASRM allow it?
The ASRM has not addressed fully the ethical implications of cloning.