United Spinal continues to support research that will make progress toward finding a cure for paralysis, prevention of secondary complications of SCI. To this end, United Spinal supports cutting edge research, including tightly regulated embryonic stem cell research and therapeutic human cloning. Under no circumstances does the United Spinal Association endorse the use of cloned embryos for human reproduction.
Embryonic Stem Cell Research
What Are Embryonic Stem Cells?
Your body is composed of millions of cells. For the most part, cells are highly specialized and cannot change. For example, a skin cell can only perform the functions of a skin cell. Its progeny can only be skin cells. Although research is still being conducted, there is currently no means of making a skin cell become or produce anything other than a skin cell.
Stem cells, on the other hand, are the precursor cells to the more specialized cells such as skin cells. With biochemical manipulation, these cells can be forced into becoming other types of cells. Adult stem cells, such as those found in bone marrow, can be useful for biomedical research — an idea that has not sparked controversy. However, adult stem cells generally can only differentiate into a certain range of cells. On the other hand, stem cells taken from human embryos are not limited in this way. They have the potential to become any type of cell in the human body.
Current Federal Policy
In August of 2001, President Bush announced that the Administration would provide federal funds for embryonic stem cell research provided that such research is performed using only stem cell lines that already exist. In other words, no new embryonic stem cell lines can be produced or used using federal funds. This policy does not have an impact on research performed with private or even state funds.
Why Embryonic Stem Cell Research?
• Because embryonic stem cells can differentiate into any type of cell, they hold the greatest promise in curing and treating the widest variety of diseases, including SCI. For example, scientists have already shown that embryonic stem cells can be manipulated into insulin-producing cells, which has allowed treatment for type-1 diabetes.
• Currently, there are thousands of human embryos left over in vitro fertilization that will be destroyed. Embryonic stem cell research is a positive way to use them, rather than destroy them.
• This type of research is already being conducted in other parts of the world. Embryonic stem cell research would allow the US to maintain its status as a world leader in scientific and biomedical research.
Human Cloning
What is Human Cloning?
Human cloning, also called somatic cell nuclear transfer (SCNT) is the production of an embryo from a somatic cell, i.e. a cell other than an egg and/or sperm cell. SCNT consists of taking the nucleus, which houses the genetic material of the cell, and transplanting it into an unfertilized egg cell that has had its nucleus removed. Unlike sex cells, which only have half the donor’s genome, somatic cells contain the full complement of genes from the individual. Therefore, the product of SCNT is genetically identical to the donor.
SCNT can be used for three purposes: biomedical research, tissue engineering and reproduction. Although the beginning steps of these three types of cloning are the same, the end results are very different. In so-called “therapeutic cloning,� the embryos are allowed to grow for up to one week, after which the stem cells are harvested for research and the remaining material is destroyed. At this stage of development, the embryo is composed of 150 cells and is not visible to the naked eye. Contrast this with the approximately 50 trillion cells that make up the adult body.
Tissue engineering is another form of therapeutic cloning. Because it is genetically identical to the donor, the SCNT product can be used to engineer body tissues to replace or repair damaged tissues without having to worry about rejection. For example, cells could be taken from any cell in the body of a paralyzed individual, implanted via SCNT, and stimulated to grow into nerve cells, which could then be transplanted into the individual to replace the damaged nerve cells. Although this technology is in its infancy, it has the potential to become the greatest advances in treating and curing diseases.
On the other hand, in reproductive cloning, the SCNT product is implanted into a woman’s uterus and allowed to develop into baby. Dolly the sheep was created by sheep reproductive cloning.
Why Therapeutic Cloning?
• Therapeutic cloning would provide a constant source of stem cells for research without having to destroy fertilized embryos.
• Because the product of SCNT is genetically identical to the donor, it could be used to develop other cells for implantation to treat or even cure diseases without having to worry about rejection.
• As with embryonic stem cell research, therapeutic cloning is being carried out in other countries. To maintain our image as a scientific and biomedical leader, the US must allow, and highly regulate, therapeutic cloning.
Recommendations
• Support S. 303, The Human Cloning Ban and Stem Cell Research Protection Act, which would prohibit the implantation of cloned human embryos while protecting valuable biomedical research.
• Support H.R. 801, The Cloning Prohibition Act, which would prohibit human reproductive cloning and would require the Institute of Medicine to conduct research into the efficacy of human embryonic stem cell research and therapeutic cloning.
• Oppose H.R. 534/S. 245, The Human Cloning Prohibition Act, which would outlaw all human cloning, including therapeutic cloning and would greatly impede the progress of biomedical research into the cure and care of spinal cord injury and disease.
