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In our era of electric cars, computers that fit into our hand, and cell phones that take pictures many of us look to science and technology to fix our problems and make life a little bit easier! Some thought it would be worth it to map out every individual chromosome of the human body. Granted, that is only about twenty three pairs of chromosomes. Nonetheless, that is over thirty thousand genes. Others wondered if a cell could possibly be manipulated to be formed into a specified desired cell. These questions arise in the study of stem-cell research. In November 1998 researchers made scientific break throughs' by isolating human stem-cells. Stem-cells are new cells that have not yet become specialized, such as becoming muscle or blood cells, for example. Every stem-cell has the potential to become any one of the body’s hundreds of types of tissue. Scientists agree that stem-cell research could change the face of medicine. If researchers learn to unlock stem-cells’ potential to develop into specific types of tissue, experts say, the potential outcomes or uses of these cells could be earth shattering. So far, the only stem-cells that have been isolated have come from fetuses that were aborted or from embryos that were discarded by fertility clinics. This raises moral and ethical questions about the source from which stem-cells come. Anti-abortion groups have set themselves “eye to eye” against such research. They find the idea of harvesting cells from unborn humans unacceptable. For years, Congress has banned federal funding for research on human embryos. (Couzin, 68). Yet, progress in stem-cell research and the medical applications it promises have pulled many scientists, lawmakers, and groups together in renewing calls to end the Congressional ban on federally-funded embryo research. Many say that days-old embryos are not human and do not need special protections. Others say medical advances made possible through stem-cell research outweigh concerns about embryos. Critics of the ban say that forbidding government-funded scientists from conducting stem-cell research will greatly retard medical advances. Moreover, if stem-cell research is put away or left to the private sector, the government will lose it’s ability to watch the development of an ethically sensitive technology (Issues and Controversies On File 329.) But what exactly are stem-cells, and how are they understood? About 30 hours after a woman’s egg, or ovum is fertilized by a man’s sperm, the newly formed zygote begins to divide. During initial cell divisions, all of the cells of the embryo are similar. These first cells are called totipotent stem-cells, because they have the ability to form the total number of cells necessary to become a human being. After one week, the embryo contains more than one hundred cells clustered in a hollow, ball-like structure called a blastocyst. By this time, the cells of the blastocyst have begun to differentiate, or take on different roles. The outer cells, called the trophoblast, will develop into the placenta, the embryo’s life support system. The other cells called the inner cell mass, are the embryonic stem-cells used in research. Scientists call these cells pluripotent, because they can give rise to many, but not all, types of cells (For example they cannot form the placenta). If the blastocyst successfully implants into a woman’s uterus, those pluripotent stem-cells will form the embryo and eventually become all of the body’s specialized tissues, such as blood, hair and skin (Viegas 10-12). When isolated in the lab, stem-cells divide indefinitely, making them an almost endless resource. Scientists say that if they can learn how to direct these cells to become specific tissues, the technology could be used to treat almost any disease. In particular, the cells could be used to treat diseases that are caused by deficiencies of a specific type of cell, such as diabetes, caused from a lack of insulin-secreting cells in the pancreas.
Approximate Word count = 2503
Approximate Pages = 10
(250 words per page double spaced)
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