Stem cell research will help scientists learn how to develop cells and tissue to cure disease. Over many years, scientists have demonstrated that they may learn how to induce these cells to differentiate into many different cell types. Accomplishing that would enable scientists to create new, healthy cells and tissue for transplantation to replace damaged or dead tissue.
But one major problem with developing disease therapies with stem cells is the body's immune response system. 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. If a patient's own cells were the source of stem cells used to create therapeutic cells or tissues, it is believed that immunological rejection could be avoided since the cells and tissues would genetically match his own.
Therapeutic cloning 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.
Thus, cloning is vital to realizing the potential of stem cell research and moving it from the lab into the doctor's office.
SCNT involves removing the nucleus of an egg cell, replacing it with the material from the nucleus of a "somatic cell" such as a skin cell and stimulating this cell to begin dividing.
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. Once the cells begins dividing, stem cells can be extracted from it days later, just as they can be extracted from embryos created through in vitro fertilization. These stem cells - or the specialized cells derived from them - will be a genetic match to the patient. Therapeutic cloning refers to the removal of a nucleus from almost any cell in an adult body.
These are somatic cells and the nucleus contains genetic material. This genetic material can then be transferred to an unfertilized egg that has also had its nucleus removed. Once reconstituted, the egg begins to divide. After days, embryonic stem cells begin to form. These stem cells can then be harvested and used to create cultured stem cells that are genetically identical to the individual with the original somatic cell. Here are some of the pros and cons of therapeutic cloning to consider when evaluating this practice.
It has the potential to create organs. There are more than , people in the United States and countless others around the world who are waiting on an organ transplant right now. The process of therapeutic cloning could be directed so that these vital organs could be created. Not only would this process eliminate wait times, it would also reduce costs.
Tissue rejection is no longer a threat. Therapeutic cloning provides an exact match to the individual who has a tissue or organ need. Even for non-organ related issues, such as replacing the skin of a burn patient, rejection becomes a minimal issue because of this process. Even though the new tissues come from a new embryo, the cells divided through the somatic materials that were previously harvested so a direct match is achieved.
It may help to treat genetic diseases. Somatic cells do carry the same DNA information as the individual, so any genetic concerns would also transfer. What if scientists could alter the genetic sequences to correct the issues that are causing a disease or disorder for the individual through the therapeutic cloning process?
As the abortion debate has demonstrated, the issue of the moral status of human embryo is interminable - it will never likely reach resolution on rational grounds. Views on the moral status of the embryo span a spectrum.
Human embryos are either mere tissue worthy of no moral respect, or they are worthy of some respect, or worthy of the same moral respect we accord the adult human being.
The statement also implies, however, that moral concern and respect for the developing embryo increases with the progressive development of the embryo and subsequent fetus.
This position places the ELCA squarely in the troubled middle, needing to move from undefined, if not unknowable assumptions, to ethical arguments about use of embryos that balance respect for the embryo with potential benefits, to policy recommendations about uncertain outcomes.
Even if one grants that certain limited ES cell research may be justifiable, such as using embryos destined for destruction from in vitro fertilization clinics or already-created ES cell lines, the use of cloning techniques is ethically more troublesome. First of all, cloned embryos are created merely for the purpose of research and ultimate destruction.
Creating embryos merely as a means - for whatever laudable purpose - fails grant them any sort of respect. Only if we have truly subverted our Christian faith to a faith in medical progress and all its rituals and promises can we find a way to respect what we destroy as some kind of honorable sacrifice.
Defenders might call it the necessary first step toward greater advances. But very little is known about embryonic stem cells. Talk of cures for Parkinson's and Alzheimer's disease rouses hope. More importantly, for researchers and biotechnology venture capitalists, such talk raises a wave of expectation and political pressure that places those with less enthusiastic stances in the position of appearing morally blameworthy for inhibiting progress against suffering.
The egg is stimulated to divide into a blastocyst early embryo with no more than about cells that has an identical genetic make-up to the original donor nuclear DNA a clone. SCNT does not involve reproduction since sperm is not used in the technique and therefore provides an alternative method of obtaining stem cells to be used in therapy or in research. Embryonic stem cells ESC are undifferentiated cells from an embryo and have the ability to give rise to all of the tissues found the body.
There is ethical and societal controversy surrounding the production of ESCs because production requires the destruction of viable human embryos.
On March 7, then President Clinton issued a memorandum that stated: "Recent accounts of advances in cloning technology, including the first successful cloning of an adult sheep, raise important questions.
They potentially represent enormous scientific breakthroughs that could offer benefits in such areas as medicine and agriculture.
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