Stem Cells. What Are Stem Cells? Sources for Stem Cells. Stem cells. Medical Ethics 1. Cells able to develop into nearly any other type of cell.

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1 Stem Cells What Are Stem Cells? Cells able to develop into nearly any other type of cell. Adult stem cells found in skin, gut, blood Embryonic stem cells found in very early development of embryo (when it has about 100 cells) Embryonic germ cells originate in reproductive cells of fetus. From adults Sources for Stem Cells Least controversial but perhaps least promising. Fetal germ cells following abortion Embryos created by IVF (in excess); no longer needed by couple Embryos created by IVF for purpose of research Embryos created asexually by somatic cell nuclear transfer. Cloning-for-research. (Sometimes called therapeutic cloning ) Medical Ethics 1

2 Factual Issues How much promise to prevent and cure disease does stem cell research have? Would cells derived from adults work just as well as those from embryos? Are there enough stem cell lines already created or do we need more for research? Would using otherwise discarded fetuses provide an incentive for abortion? Can adequate research proceed without federal funding? Ethical Issues What is the moral status of a human (pre-) embryo? Does it make a moral difference whether created for purpose of research? Does it make a moral difference if embryo would otherwise be discarded? What should public policy be in an area full of moral and religious controversy? Embryonic Stem Cell Research: To Fund or Not to Fund? Do not fund (prohibit?) use of any stem cells even if already created (because implicated in killing embryo) Fund use of embryonic stem cell lines that have already been created. (No funding for the creation in future.) Fund creation of stem cell lines but only from embryos already in storage and otherwise to be discarded. Fund creation of stem cell lines from future embryos/fetuses if they would otherwise be discarded. Fund creation of stem cell lines from any embryo, including those created for this purpose (perhaps through cloning) Medical Ethics 2

3 Pres. Bush s Decision Do not fund (prohibit?) use of any stem cells even if already created (because implicated in killing embryo) Fund use of embryonic stem cell lines that have already been created. (No funding for the creation in future.) Fund creation of stem cell lines but only from embryos already in storage and otherwise discarded. Fund creation of stem cell lines from future embryos/fetuses if they would otherwise be discarded. Fund creation of stem cell lines from any embryo, including those created for this purpose (perhaps through cloning) Nat l Bioethics Advisory Commission (under Clinton; expired 10/2001) Do not fund (prohibit?) use of any stem cells even if already created (because implicated in killing embryo) Fund use of embryonic stem cell lines that have already been created. (No funding for the creation in future.) Fund creation of stem cell lines but only from embryos already in storage and otherwise discarded. Fund creation of stem cell lines from future embryos/fetuses if they would otherwise be discarded. Fund creation of stem cell lines from any embryo, including those created for this purpose (perhaps through cloning) National Bioethics Advisory Commission (Appointed by Clinton; not in this edition of Munson Adult cells should not be considered an adequate alternative to embryonic Embryos deserve respect but scientific and clinical benefits of stem cell research should not be foregone. Development of public policy in a morally contested area is not a novel challenge for a pluralistic democracy [as in U.S.] Medical Ethics 3

4 Use of Aborted Fetuses OK to fund derivation and use of stem cells from aborted fetuses. Must separate the decision to abort from the decision to donate Can this really be done if women know that aborted fetuses are used? But would it really influence a decision whether or not to abort? Use of Excess Embryos OK to fund use of embryos remaining after fertility treatment The ban on federal funding of embryo research should be lifted: conflcits with several of the ethical goals of medicine especially healing, prevention, and research. Objection (accepted by Pres. Bush): OK to fund use of already created stem cell lines but not their creation. Research interests dictate against this separation. Use of Excess Embryos Must separate couple s decision to discard embryo (rather than use or donate to another couple) from decision to donate. Couple cannot direct to whom stem cells will go (to deny an incentive) Medical Ethics 4

5 President s Bioethics Council In your text; appointed by Bush Cloning to produce children should be prohibited ( reproductive cloning ) Cloning for research ( therapeutic cloning ) Majority view: Four-year moratorium Minority view: Approve right now Embryo has intermediate moral status, not equivalent to a person but deserving respect Another group: embryo has no special moral status New President s Council Established by Pres. Bush Unanimous in opposing cloning for reproduction Might we someday want to endorse this Sex: Male Female Origin: Sexual Cloned If cloned, relation to donor: New President s Council Established by Pres. Bush Divided: 3 views on cloning for research Enthusiastic endorsement Favor with serious moral concern Oppose Medical Ethics 5

6 Enthusiastic Endorsement Promise of great benefit to humankind Moral issues no different from other kinds of research; e.g., informed consent (from donors of eggs and somatic cells) Presumably, embryo not a person with rights Minority (7 members): ban only cloning to produce children and allow cloning for research without delay Endorse with Serious Concern Embryo has intermediate moral status : not a person but worthy of respect EB: seems to correspond to Islamic position presented by Abdalazis Sachedina Status of fetus: limit to first 14 days Concern about exploitation of women Concern about deliberate creation of human life, but it s not for purpose of destruction but to benefit humans. Majority view: ban on cloning-to-produce children for 4 years. Why oppose embryonic stem cell research? Cloned embryo is a person with rights Special respect means nothing if it can be destroyed Crosses a boundary: creating human life for purpose of research Opens door to cloning for children. Then we d have to demand destruction of embryo. Medical Ethics 6

7 Still Pending NBAC, Bush, and BioethicsCouncil mainly discussed federal funding Congress now considering a ban on all cloning, both for reproduction and for research. UN just rejected US proposal to ban cloning for research as well as reproduction Kass initially favored allowing cloning for research but changed his mind Could the two be adequately separated? What if research embryo implanted? The Michigan Situation Proposal 2 would allow embryonic stem cell research in Michigan: Medical Ethics 7