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Stem cell research is the most promising path to curing many severe diseases and disabling medical conditions. It may yield remedies for such conditions as Parkinson’s and Alzheimer’s diseases, juvenile diabetes, spinal cord injury, MS, ALS, and certain forms of cancer and heart disease.
Stem cells are unspecialized cells that can develop into more mature, specialized cells. They are found in embryos during their first few days of development, in fetal tissue, and more rarely, in some adult organs. Scientists work with both embryonic and adult stem cells, but embryonic stem cells are the more promising because they are “pluripotent,” meaning that they have the potential to differentiate into tissue of almost any organ (brain, liver, heart, pancreas, etc.) of the human body. Adult stem cells, on the other hand, are merely "multipotent" meaning that they generate just a few tissue types, and are difficult to extract and grow, and many tissues cannot be derived from adult stem cells. Regenerative medicine, based on embryonic stem cell research, aims to use pluripotent stem cells to heal severe illnesses and injuries. The hope is that we can grow stem cells in laboratories to form specific tissues, such as brain, heart, lung, kidney or pancreatic tissue, which could then help repair damaged and diseased organs or provide alternative to organ transplants. Many of the illnesses that are targets of stem cell therapy have few or no treatment options, so millions of Americans are looking to stem cell research as a promising path to new, effective treatments.
But unfortunately, this research has gotten tangled in politics and is being delayed and under funded by an executive order from the President. There is an effort in the U.S. Senate to ban it or place a four year moratorium on it.Portraits of hope
Many of the illnesses that are targets of stem cell therapy have few or no treatment options, so millions of Americans are looking to stem cell research as a promising path to new, effective treatments.
How Does Stem Cell Research Lead to Cures?Some children are born with organs that do not work right. A child with juvenile diabetes, for example, has a pancreas that does not generate enough insulin – a hormone needed by the body in order to digest sugars.
Adults too sometimes have cells or entire organs that have become damaged so that they no longer function well. In the brain of a person who has Parkinson’s or Alzheimer’s disease, for example, cells no longer work in the normal way. In a spinal cord injury, crushed or damaged cells cause paralysis. In a heart attack, heart muscle is destroyed and replaced by useless scar tissue. In each of these cases, the result is illness, disability, and suffering.
Doctors and scientists have long been looking for a way to replace damaged or worn-out tissue in the human body with new healthy tissue, thereby giving patients a new chance to live. The most promising path to cures is the regeneration of differentiated tissue from embryonic stem cells. Research using these cells is the most promising path to finding the cures needed by the nearly 100 million Americans afflicted by conditions ranging from Parkinson’s and Alzheimer’s diseases to juvenile diabetes, MS, ALS, and spinal cord injury.
There are today two main sources of pluripotent stem cells that can be used to advance the search for cures:
-Scientists can use stem cells from left-over embryos that would otherwise be discarded from fertility clinics. From these cells, healthy new tissue can be formed to replace the tissue that an illness or injury has damaged or destroyed.
About 400,000 frozen embryos are currently being stored in our nation’s fertilization clinics. Most of them will be eventually thrown away. Instead, they could be used to create new stem cell lines and thereby contribute to life-saving medical research. But when Bush became president, he banned federal funding for research using these embryos. This decision is preventing embryonic stem cell research from advancing to find cures. In fact, the small number and poor quality of currently available stem cell lines are discouraging scientists from even entering the domain of stem cell research.
-Scientists can use therapeutic cloning to generate stem cells for research to find cures. The technical term for therapeutic cloning is “somatic cell nuclear transfer” (SCNT). Scientists remove the nucleus of an unfertilized egg cell and replace it with the genetic material from the nucleus of a "somatic cell" (a skin cell, for example). Then they stimulate this cell to begin dividing. No sperm is involved in this process, and no embryo is created to be implanted in a woman’s womb. The clump of cells resulting from this process is stored in a petri dish, never leaves the lab, and continues to divide for up to seven days. The stem cells generated in this way won’t become a human being, but they can potentially develop into specialized cells – brain cells, blood cells, pancreatic cells, etc. -- that are useful for treating medical conditions ranging from childhood Diabetes to Alzheimer's, Parkinson's, heart disease, and spinal cord injury.
SCNT would produce stem cells that are genetically identical to a patient’s original cells. As a result, the patient’s immune system would be much less likely to reject the transplanted or transfused cells, making it easier to use them for restorative purposes. For this reason, SCNT-generated tissue solves problems that make donor tissue transplants difficult.Therapeutic cloning (or SCNT) research is ethical and safe. It should not be confused with reproductive cloning to produce a baby, which is inadvisable and dangerous. Therapeutic cloning (SCNT) produces no cloned individual, but only cell tissue that can be used to heal an individual.
Therapeutic cloning research is endorsed by the American Medical Association, the National Academy of Sciences, the Association of American Universities, and many other medical, scientific, and educational associations. Almost all scientists who work in the domain of basic biomedical research view therapeutic cloning (SCNT) research as crucial. The National Academy of Sciences has concluded that therapeutic cloning "offers great promise for treating diseases.... closing these avenues of research may have real costs for millions of people who now have these diseases."
In their statement of support for therapeutic cloning research, forty Nobel Laureates say that SCNT research is needed not only to develop cell-replacement therapies, but also to increase our understanding of how inherited genetic predispositions lead to a wide variety of diseases. A deeper understanding of how diseases arise will help us to cure them.
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