James A. Leach: “the possibility is real that embryonic stem- cell research represents the greatest breakthrough in the history of…”

“the possibility is real that embryonic stem- cell research represents the greatest breakthrough in the history of science. It is, therefore, important that we understand the medical and moral issues at stake. In 1998, University of Wisconsin scientists for the first time isolated embryonic stem cells in a laboratory. These cells, 30 to 34 in number, are derived from a blastocyst, which is a group of 150 to 200 cells smaller than the dot at the end of this sentence. A blastocyst, in turn, is derived from a single cell known as a zygote, which comes into being after a sperm and an egg combine. Blastocysts have been created outside of the body in cell cultures for decades in fertility clinics. More than 400,000 are known to exist in frozen form. Thousands are discarded as medical waste and millions are eliminated naturally every year. The reason the scientific community is so excited about embryonic stem cells is that they are pluripotent. Unlike other stem cells, they are capable of continuously dividing and being coaxed into forming virtually any of several hundred types of body cells. Health research is conducted in stages--mice before people. At the moment, scientists are encouraged by the results they have obtained from the animal kingdom. Research on mice, pigs and monkeys is so promising that scientists can envision the possibility of creating ``cellular repair kits'' for the human body.…”