and divide further. These cells maintain the ability to form cells ranging from muscle to blood to .
nerve, and potentially any body cell type, increasing the potential promise for treatment and .
curing of diseases. Stem cells may develop into insulin-producing cells that can be used to treat .
those afflicted with diabetes, into heart cells that could repair cardiac muscle damage after heart .
attacks or strokes, or even into nerve cells for treatment of Alzheimer's and Parkinson's diseases .
and repair of spinal-cord injuries.
The controversy of this ethical debate begins at the source. In order to retrieve stem cells .
used to treat patients, living human embryos must be destroyed. It comes down to a decision .
between saving lives and relieving the suffering of ill patients or preserving the human embryos .
- one life for another. .
Scientists can obtain the necessary embryos needed for stem cells in four ways: .
through fertility clinics, aborted fetuses, cloning, or made-to-order embryos. The first option .
which is also the least controversial, involves in-vitro fertilization, in which clinics repeatedly .
fuse more than one egg with sperm in order to implant a fertilized egg. As a result, there are .
thousands of unwanted embryos left behind in stored freezers at fertility clinics. John Gearhart, .
one of the scientists credited with being the first to culture stem cells, used fetuses donated by .
women from abortion clinics as his source for research. The donated fetuses are even a clearer .
representation of human life in comparison to the embryos; however, both have been used in .
stem cell research. In this case, the donated fetuses had already been aborted by their mothers, .
but this type of research may unintentionally promote more occurrences of abortion, most .
especially that of late-trimester. Cloned human embryos are also an option as sources for stem .
cells, as are made-to-order embryos, created specifically for the purpose of having more sources .
