Embryonic stem cells are derived from human embryos about one week after fertilisation. At this stage of development the embryo is referred to as a blastocyst who, under a microscope, looks like a hollow ball with a cluster of cells inside. These cells are stem cells that will eventually grow into every tissue type in the body as the embryo develops. For this reason scientists are very interested in experimenting on embryonic stem cells. However, while certain therapeutic benefits have already been achieved using adult stem cells, we have yet to see a positive treatment result from the use of embryonic stem cells.
Much controversy surrounds embryonic stem cell research and with good reason: the human embryo is destroyed in the process of extracting its stem cells. Opponents of this type of research believe that this constitutes the destruction of human life and argue that destroying embryos for the purposes of harvesting their parts reduces early human life to the status of research material.
The fundamental ethical problem with research on human embryos is that this type of research will assure the destruction of many early human lives. It is not possible to extract stem cells from the living human embryo without destroying him/her in the process. International documents such as the Nuremburg Code, the World Medical Association’s Declaration of Helsinki, and the United Nations Declaration of Human Rights reject the use of human beings in experimental research only if there is clear benefit for the human subject.
An ethic which condones research using human embryos violates the standards set out by these documents. It also undervalues human life, damages the integrity of science and medicine, and degrades society.
The extraction of stem cells from the human embryo, and transformation of these cells into viable stem cell lines is, in any case, fraught with problems. Most attempts end in failure. Harvard university reported in 2004 that its researchers required 344 IVF embryos to derive just 17 usable embryonic stem cell lines. That is a productivity rate of about one stem cell line for every twenty attempts. So we can see that even generating stem cells from embryos is an extremely inefficient process, and it means that countless human lives will be lost to acquire just a few stem cell lines for researchers to experiment with. Furthermore, these stem cell lines have failed to yield any results
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