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The Science of Stem Cells

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The Science of Stem Cells In late 1998, a group of scientists led by University of Wisconsin-Madison developmental biologist James Thomson became the first in the world to successfully isolate and culture human embryonic stem cells. Because embryonic stem cells are the precursor cells to all other cell types in the human body, this accomplishment has set the stage for a revolution in medicine and basic biology. The promise of stem cells lies in their ability to be cultured in the laboratory and, ultimately, directed to become specific types of cells or tissue that can be used to treat a host of cell-based diseases such as juvenile diabetes, Parkinson's and heart disease. Stem cells arise early in development, when embryos are less than a week old, and exist there in an undifferentiated state for a very short time before going off to become other types of cells. In the course of development, they ultimately become skin cells, neurons, muscle, blood cells and every other of the 220 cell types that make up the tissues and organs in the body. In their undifferentiated state in the laboratory, stem cells show an ability to divide indefinitely. The five cell lines established here in 1998 continue to divide, and show no evidence of a diminished ability to make more cells. In addition to the potential for advances in health care, stem cell research also offers science its only window to the earliest stages of human development. The opportunity to study events at this stage offers insight into the unknown cellular events that cause birth defects and contribute to infertility. Stem cell research could also yield powerful new methods for screening and testing new drugs. By creating pure populations of specific kinds of cells and exposing them to new chemical compounds, it is possible to better explore issues of drug safety and efficacy before further testing is done on animals and humans. ...read more.


Q: Given the president's restrictions, how can regulators be sure federal funds aren't used on stem cells created after his policy is enacted? A: That's unclear. Bush did not specify how scientists will know if certain cell lines are "pre-approved" or not. It can be difficult to "fingerprint" cell lines to ensure their provenance. With cells being mailed from lab to lab, lineages could get mixed up. Q: Where do stem cells come from, and why are they so important? A: They are retrieved from the core of five-day-old human embryos, typically left over from invitro fertilization processes used by couples trying to have a baby. Stem cells can morph into virtually every kind of tissue, providing a potentially bottomless source of replacement parts. Q: Can't stem cells also be found in adult tissues? A: Yes. But scientists believe embryonic stem cells are more versatile and therefore hold greater promise in curing diseases and injuries such as spinal cord damage. The Stem-Cell Compromise By Harold Varmus and Douglas Melton Mr. Varmus, director of the National Institutes of Health from 1993 to 1999, is president of the Memorial Sloan-Kettering Cancer Center. Mr. Melton is a professor of molecular and cellular biology at Harvard and studies embryonic stem cells with support from the Juvenile Diabetes Research Foundation. When George W. Bush addressed the nation last week about embryonic stem cells, the big news was the delicate compromise the president had struck -- allowing federal funding to go forward, but only on some 60 cell lines derived from embryos that had already been destroyed. Since then, the focus has shifted from the compromise to questions about the 60 cell lines themselves. Will we actually be able to answer the most pressing questions with these 60 lines? Will they really be accessible to federally funded scientists? And if not, what happens to Mr. Bush's grand compromise? Crucial Issues The political significance of the number is obvious: If enough cell lines are already available for researchers to take the necessary next steps, then the president is justified in claiming (at least for the next several years) ...read more.


The stem cell/cloning controversy raises, once again, the fundamental issue of personhood and the ensuing considerations of how human persons should be treated. Unfortunately, Christians cannot turn to the Bible for a specific verse to tell us if the embryo has the same rights as other humans. However, when Scripture mentions the unborn, the context is almost always one of God's protection for them and His vision for their lives (Psalm 139:13-17; Isaiah 44:1-2; Jeremiah 1:3). Human dignity arises from our being created in the image of God. If we ask "Who is an image of God?," we may receive no easy answer. But Jesus was asked, "Who is my neighbor?" His reply with the parable of the Good Samaritan redirects the question (Luke 10:29-37) and emphasizes our responsibility to care for all human beings in whatever ways we can. Are we acting as good neighbors to these embryos? Do we reflect the image of God when we endorse the destruction of other human beings? Hardly. It is indeed difficult to accept the disability or premature death of any human being because such tragedy marks the loss of potential. Who might this person have become? What might he or she have accomplished? Yet precisely the same potential is lost when a human embryo, cloned or not, is torn apart to supply stem cells for the benefit of another. Who would these embryonic beings have become, if only they had been protected and nurtured? Instead of sanctioning their sacrifice, those who brought these embryos into being should act as caretakers, nurturing and protecting these tiny human lives. In that way, they act as faithful images of God, reflecting His character to the world. Endorsing the destruction of human embryos fails miserably to reach this end, as it makes it ever easier for society to abdicate its responsibilities to the weak and vulnerable at all stages of development. Policies which promote human cloning and research on stem cells derived from human embryos reflect ominously on the state of a society and the values which characterize it. Donal O'Mathuna - Mount Carmel College of Nursing ...read more.

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