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Stem Cells?

  1. May 11, 2005 #1
    Are stem cells (used in research) derived from frozen embryos from people who wish to do in vitro fertilization?
  2. jcsd
  3. May 12, 2005 #2


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    There are different sources from which stem cells can be isolated: spare IVF embryos, cloned embryos, adult tissues, cadavers, aborted fetuses, umbilical cord blood.

    So yes: some stem cell lines are derived from frozen embryos created during an IVF procedure, the parents have to give consent in order to release the embryos.
  4. May 14, 2005 #3
    it depends on whether you mean embryonic stem cells or somatic (aka adult) stem cells. nowadays, due to their controversy, most people mean stem cells as "embryonic".

    the only source of an embronic stem cell is an embryo in the blastocyst stage of development. (the commercial source of these are IV fertilization: typically multiple embryos are made in vitro, yet the parents desire only 1 child). 2 other classes of pluripotent stem cells are embryonic germ cells (derived from the fetal gonads) or embryonic carcinoma cells, which are cancerous cells derived from sex cells that in many ways resemble ES cells.

    cord blood, bone marrow, etc. are all sources of adult stem cells, a completely different beast altogether. these cells are not pluripotent, but rather can only differentiate (as far as anyone knows) into a limited set of cell types.

    the test for potency is to inject the cells into the testes of a mouse. if they are pluripotent, then this will cause a teratoma in the mouse, a rather poorly differentiated tumor that will contains diverse tissues. teratomas frequently contain hair, teeth, blood vessels, parts of organs, and sometimes even eyeballs.
  5. May 17, 2005 #4

    im not exactly sure if they are from frozen embryos, but i know that stem cells are derived from parents who dont want their embryos so the doctors remove the embryo and take form it the stem cells which leads to the death of the embryo which i think is unethical. :smile:
  6. May 18, 2005 #5


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    It is true that some lines have come from aborted embryos, but current ethical practices recommend that embryonic stem cells come only from IVF embryos that are in excess and that will otherwise be discarded. There is actually a bill in congress (in the US) right now which, if passed, would reinstate funding of stem cell research and allow researchers to use more currently developed lines thatn are allowed to be used right now (the older lines have problems with them that newer lines don't have). If it is passed, it will include language that specifically requires embryonic stem cells only be obtained from excess IVF embryos that would otherwise be destroyed after a couple has had their children via this method, and must be obtained with the consent of the parents and no monetary compensation is provided (to prevent couples from "selling" their embryos).

    As has already been mentioned, there are other types of stem cells that don't come from embryos at all, such as from adult tissues or the umbilical cord (the side still attached to the placenta after it is cut at birth).
  7. May 18, 2005 #6
    the only stem cells that come from aborted fetuses are embryonic germ cells (from the gonal ridge in the +8 week embryo). ES cells do not.
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