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Stem cell research

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== '''AN ORTHODOX CHRISTIAN VIEWPOINT ON STEM CELL RESEARCH''' =={{cleanup}}===What Are Stem Cells?===
The human body is made of billions and billions of cells, which have specific shapes, particular structures, and different functions. Cells of the same type make tissues, and tissues make organs. Cells, tissues, organs, and systems make the human body. No matter how simple or complex an organism is, the cell remains the structurally and functionally basic unit of life (there are even unicellular organisms, like bacteria.)
Stem cells are a particular kind of cells, with two major characteristics:
'''1.''' # they are unspecialized cells that can divide over and over for very long periods of time;  '''2.''' # under certain conditions, they can be induced to become cells with special functions (like muscle cells, liver cells, neurons, etc.).
Stem cells are naturally occurring in the human body (and other living organisms) at all levels of development. As organisms develop, stem cells become specialized types of cells. They are harder to find and lose much of their ability to differentiate. Stem cells are the way the organism generates all the specialized cells needed for development and functioning.
There are two kinds of stem cells used in biomedical research:  '''1.''' ''Embryonic Stem Cells'' - which occur only in early development;
#''Embryonic Stem Cells'2.''' - which occur only in early development;#''Adult Stem Cells'' - occurring in adult organisms.
In the fetus, stem cells in developing tissue give rise to the multiple specialized cell types that make up the human body. In some adult tissues, such as bone marrow, muscle, and brain, discrete populations of adult stem cells generate replacement cells. While both types of stem cells are very important for biomedical research, the use of embryonic stem cells raises most of the bioethical issues.
After fertilization, the zygote (fertilized egg) divides several times. Any of the cells resulted from these divisions can give rise to all the cells needed to make up an adult organism. Basically, any of these cells can “act as an embryo.” These cells are called ''totipotent stem cells''.
After 3 to 5 days, prior to implantation into the uterine wall, the embryo achieves a stage called blastocyst. In the interior of the blastocyst, there is a cluster of about 30 cells called the inner cell mass. The cells that form the inner cell mass of the blastocyst are called ''pluripotent stem cells''. They have lost the ability to differentiate to all cell types needed for a complete embryo development (up to 14 days post-fertilization).
As embryonic development proceeds, stem cells lose their pluripotency. In adults, the remaining stem cells only differentiate into cell types specific to the tissue in which they reside (some recent studies seem to prove the contrary.)
Adult stem cells give the body its ability to repair and replace the cells and tissues of some organs. Adult stem cells are rare, and their origin in mature tissue is not yet completely understood. It is supposed that they are somehow set aside during fetal development and restrained from differentiating. Adult stem cells are dispersed in tissues throughout the mature organism and behave very differently depending on the local environment. Some recent studies focus on the ''plasticity'' of the adult stem cells, which is the ability to differentiate in specialized cells of another tissue.
The embryos used in stem cell research come from three major sources:  '''A.''' ''In Vitro Fertilization'' - some of the embryos used in human stem cells research were initially created for infertility purposes through in vitro fertilization procedures. When they were no longer needed for that purpose, they were donated for research with the informed consent of the donor.  '''B.''' ''Somatic Cell Nuclear Transfer'' - embryos can be created by transferring the nucleus of a donor cell into an enucleated oocyte. The embryo will be genetically identical to the donor.  '''C.''' ''Embryonic Germ Cells'' are obtained from aborted fetus tissue.
# ''In Vitro Fertilization'' - some of the embryos used in human stem cells research were initially created for infertility purposes through in vitro fertilization procedures. When they were no longer needed for that purpose, they were donated for research with the informed consent of the donor.
# ''Somatic Cell Nuclear Transfer'' - embryos can be created by transferring the nucleus of a donor cell into an enucleated oocyte. The embryo will be genetically identical to the donor.
#''Embryonic Germ Cells'' are obtained from aborted fetus tissue.
The stem cell extraction procedure ends the ability of the embryo to develop through implantation in the uterus. The removal of the stem cells brings the existence of the embryo to an end. Stem cell research promises not only to clarify some of the fundamental processes of life, but also some very interesting therapeutic possibilities. Nowadays scientific medicine is based on drug therapy. It is dominated by antibiotics, chemotherapy, antipsychotic agents and other pharmaceuticals.
The scientific medicine of the future will be probably based on cell therapies, focused on repair and regeneration of tissues by cell transplants. In a rough way: instead of administering lots of chemical substances in an attempt to prevent cell malfunction or premature cell death, why not just replace the cells in question? Many scientists take the view that the benefits which might flow to humanity from this form of research are so great that it is important that it be allowed to proceed.
 ===The Moral Status Of The Embryo=status of the embryo==
The debate around embryonic stem cells research is sensitive and controversial. Is it ethically acceptable to destroy the blastocyst? Many Christians believe that it is not, and in order to respect every one of God’s children, they sustain that each created zygote is completely deserving of protection and ought not to be destroyed. To destroy a developing human at any stage is then comparable to murder. Most of the ethical debate around embryonic stem cell research is centered on the moral status of embryos and fetuses, as well as the significance of the source of embryonic or fetal material. Use of adult stem cells seems morally unproblematic from this point of view.
==Sources==
*Breck, John. ''The Sacred Gift of Life''. New York: St Vladimir’s Vladimir's Seminary Press, 1998.
*Louth, Andrew. ''Ancient Christian Commentary on Scripture''. Downers Grove, Illinois: Inter Varsity Press, 2001.
*Ruse, Michael & Christopher A. Pynes. ''The Stem Cell Controversy''. New York: Prometheus Books, 2003.
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