A few thoughts on stem cell research.
- embryonic stem cells still have the best viability despite the possibility of using cells from other parts of the body. As your cells devide, they poly-a tail at the end of the DNA sequence degenerates. After a few million divisions, (in an adult carrying a baby - umbilical blood) the genetic code becomes damaged and you would end up with body parts that are falling apart just like Dolly.
- bone marrow stem cells can be made to form other cell types, but they are limited by what they can become, whereas embryonic stem cells aren't.
- if you think the ethical issues around creating a small blastocyst and harvesting stem cells from it are bad, what would the ethical issues be around using a womans umbilical cord blood? Using that blood is going to be an invasive procedure with possibilities of harming the fetus. Considering the strong opposition to any interference in reproduction by science, I don't think this will be practical.
- human fetuses aren't used in stem cell research. There was a Dr. Gearhart that recovered stem cells from aborted fetuses, but at the point in which most research harvests stem cells, the cell mass is indistinguishable from that of a rodent, starfish, or guppy.