The Future of Stem Cells
Disease Research Hindered by Reproductive Cloning Threat, Experts Say
Deliberate Confusion continued...
Buried in the debate is an ethical issue. That's the question of whether the collection of human cells known as a blastocyte is a human being. If the blastocyte is healthy -- and many blastocytes formed by SCNT are flawed -- and if it is transferred into a human womb, it might grow into a fetus, though it's unlikely.
One argument advanced by some abortion opponents is that a woman's egg is a human being from the moment it is fertilized. Banning research on stem cells -- particularly on human blastocytes, even if they've never been placed in a woman's body -- might set a legal precedent for banning abortion.
"Opposition to abortion is the 900-pound monster hiding behind this confusion of stem cell research with reproductive cloning," Caplan says. "They think that if we're all frightened enough about cloning people, they can get legislation saying that embryos are human from the moment of conception. That would help them get a ban on abortion."
Cloning and Stem Cell Research
Can stem cell research proceed without cloning? Yes and no, says Alta Charo [SHARE-row], JD, professor of law and medical ethics at the University of Wisconsin, Madison.
"Cloning is something that is not essential to stem cell research," Charo tells WebMD. "Most research will go on with discarded embryos from reproduction assistance clinics."
But some important research will require the use of cloning techniques, although there might be less confusing ways to talk about it.
"It might help to get away from the issue of cloning and talk about the deliberate creation of special embryos," Charo says. "There will be a small number of experiments that cannot be done with discarded embryos. Those are the experiments that look at the genetic mechanisms of the causes of disease."
If that seems vague, Charo has a specific example: breast cancer. Two genes, BRCA1 and BRCA2, give a woman a very, very high risk of breast and ovarian cancer.
"Their alternatives are awful: We can rip out their ovaries and throw them into early menopause. We can cut off their breasts. Or we can wait and watch to see whether they develop cancer," Charo says. "The better thing is to understand what is going on to make this mutation cause cancer."
Using SCNT, cells from a woman carrying the BRCA mutation could be used to create an embryo carrying the mutation. From this embryo, scientists could obtain stem cells. And from these stem cells it would be possible grow laboratory cultures of ovarian and breast tissues.
"Now you can find out why this is causing cancer," Charo says. "And this gives you an opportunity to disrupt this sequence of events. Now you are on the way to an intervention that doesn't require mutilation of women's bodies. This you cannot do with discarded embryos."