stem cell research

Stem cell research has quickly become a hot new topic these days to debate over. One side says it’s unethical, the other side says it’s critical to the advancement of medical science. It’s hard to make up your mind before you have the facts, so here they are.
Stem cells are cells that have the ability to transform into any type of tissue cell in the human body. After a sperm fertilizes an egg, the cell they form is known as a zygote or a totipotent cell. This cell goes through numerous mitotic divisions and after about four days forms a blastocyst. This blastocyst has an outer layer and an inner layer, part of which is hollow. The outer layer grows to form what will become the placenta. The cells contained in the inner layer are known as pluripotent cells. They are what the term stem cell generally refers to. These pluripotent cells cannot survive by themselves. But they do have the ability to form most of the tissues needed fro the embryo’s survival. It is these cells that scientists are interested in. they say that if these cells are isolated away from the embryo, they can be theoretically coaxed to turn into a special type of cell, for example a nerve cell, or a brain cell, or a blood cell. But there is a hitch involved. If you take these cells out of an embryo, the embryo will die, much like if you take out the heart of a man to give to another, the donor will die. It is on this fact that the opposition to stem cell research bases its cause on, to stop the killing of embryos just for scientific research. But on the other hand, scientists say that by using this universal cell, they can develop cures fro many diseases, such as Parkinson’s, or diabetes, or heart disease. Also, the development of stem cells into certain kinds of cells is controlled by so called “on, off genes”. Scientists say that the same type of genes are responsible for the development of tumors which lead to cancer, and if research can be done on these stem cell on/off genes, and they can figure out how they work, then a cure for cancer is possible.
Not all stem cells come from embryos. So anti-stem cell researchers have proposed the idea of researching on adults, since adults also have stem cells in their bodies. But they are few in number, hard to locate, and do not represent all the types of tissue in the human body. Also, environmental conditions might have changed the condition of the adult stem cells over that person’s life. So you might say that adult stem cells could be corrupted.
Another method of obtaining stem cells is SCNT, or somatic cell nuclear transfer. In this process, a hollowed-out human egg is placed by a somatic cell of any type. These two cells are now fused together. The resulting cell is theoretically totipotent and can be used to obtain stem cells from.
I believe that stem cell research should continue, full-fledged, but with limitations. As long as the embryos are extra embryos left over after In Vitro fertilization in fertility clinics and not embryos produced just for research. Also the embryos must be taken with the consent of the couple. These embryos are extra, and will usually not be needed anymore. Also, they result in huge custody cases if the couple divorces. Why should these embryos be left in a freezer and result in civil suits when they could be helping mankind? I also believe that if the embryos develop into a fetus, stem cell extraction should stop. For me, the limit for research is the blastocyst.