The state of PGD—an update from ASH

At the 53rd meeting of the American Society of Hematology (ASH), held from December 10-13 in San Diego, there was an “education spotlight” session entitled, “Preimplantation Genetics: The Science, The Medicine, The Bioethics.” The speakers were Joyce Harper, PhD, from the University College London Centre for Preimplantation Genetics and Diagnosis (PGD), and Mark Hughes, MD, PhD, from Genesis Genetics Institute in Detroit. I’m hardly a PGD expert, so I attended to hear perspectives from people who are practicing it. The session was long on science and medicine but too short on the discussion of ethics. This was a shame because the speakers clearly have ethical worries, even though they are clearly not congruent with the concerns of most TIU bioethicists. Still, I found the session thoughtful and informative.
There was far too much for a brief blog post, but here are some highlights, first on the medical/scientific side:
1) PGD can be made on a single cell (typically 1-5), taken at any of several stages of early embryonic development. Dr. Hughes showed how he takes a single cell at the blastocyst stage (5-6 days after fertilization). Results in 24 hours, with a stated diagnostic error rate of 0.7%, and an attendant 1% post-PGD risk of a genetic-recessive disease (compared with 25% by standard Mendelian genetics).
2) PGD is most commonly used by fertile couples to try to avoid a severe genetic disease after a first affected birth or known risk based on parental genetics.
3) Genetic analysis is moving toward genome-wide arrays that can read the entire genome quickly, and at ever lower cost (currently about $2500 per genome). Dr. Hughes: “The technology now has no limitations [diagnostically]…so the question is not ‘can we?’ but ‘should we?’” [diagnose].
4) Biopsied embryos generally—but not always—do well, so the success rate of the (necessary) IVF pregnancies is reduced. The number of implantations is also reduced—e.g., 12 eggs to get 10 fertilizations, 8 embryos biopsied, 7 successfully diagnosed, 5 abnormal and 2 normal, one of those two judged viable for implantation.
5) Dr. Hughes said there were 47,164 PGD babies in the US in 2010. I thought he said born in 2010 but that number sounds high for a single year. Still, it’s a lot.
6) The most prominent “savior sibling” examples are for a disease that is curable with bone marrow transplant (BMT), e.g., sickle cell anemia (SCA). The PGD baby’s umbilical cord blood (UCB) becomes the donor blood. An example is sickle cell anemia (SCA). Dr. Hughes told the story of the family of NBA player Carlos Boozer, whose first child was cured of SCA after receiving a UCB transplant after the birth of his baby brother. Dr. Hughes is working to take this approach to SCA to West Africa at low cost.
7) For a Mendelian-recessive disease, one needs an unaffected embryo that is also an HLA (immunologic) match, with the probabilities being ¾ x ¼=3/16. In other words, 16 embryos to get 3 genetically appropriate “saviors.”
As I said, the ethical discussion was compressed, and must also be here. Clearly one worries about all the other embryos created in this process—and at least one questioner at ASH raised this by mentioning the value of all people despite disease or disability. As someone who considers himself a strong pro-lifer, I do find PGD for the most severe genetic disorders a “hard case,” and I have to admit that I am reluctant to condemn the Boozers. The speakers were most concerned about how to limit the use of PGD, medically. They are clearly uncomfortable with drawing premature conclusions or taking action on the often-uninterpretable results of a genome-wide analysis. They also raised hard cases of using PGD for otherwise treatable disease (e.g., polycystic kidney, or to obtain UCB to transplant a sibling with leukemia), using PGD to get an Rh-negative baby when mom has sensitized to Rh in a prior pregnancy, or using PGD to eliminate a cancer-susceptibility gene like BRCA-1 from the family tree (Dr. Hughes would accept, but he had debated Francis Collins, who would not permit this). Bottom line: these two professionals do seem to agree that defending the “therapeutic boundary” is important. If I read that correctly, I find it at least a bit reassuring and perhaps a contact point for engagement.
Space does not permit more here. I’m happy to try to field questions or carry on discussion through comments.

A Dispatch from A Front

I just attended the Advancing Ethical Research Conference of the group, Public Responsibility in Medicine & Research (“PRIM+R,” or “PRIMER,” because they make the “and” symbol look like a rounded “E”). Saturday’s plenary address was by Jonathan Haidt, Professor of Evolutionary Psychology at the University of Virginia. His topic: “The Intuitive Foundations of Morality (Or, Why some Research is Offensive to Some People).” Key points:
1) His introducer noted Dr. Haidt’s forthcoming book, The Righteous Mind, with the comment that Dr. Haidt research had discovered that all people are deeply flawed, morally. (I made a mental note that he should be congratulated for “discovering” original sin.)
2) Dr. Haidt described himself as an intuitionist but definitely not a cognitivist, having been thoroughly convinced by David Hume that “reason is the slave of the passions.” He described reason as the “rider” on the back of an “elephant” (emotions). (Essay assignment: compare and contrast with Plato’s chariot allegory in the Phaedrus.)
3) He identified 6 basic moral values: care (vs harm), fairness (vs cheating), liberty (vs oppression), loyalty (vs betrayal), authority (vs subversion), and sanctity (vs degradation). These, to him, are analogous to flavors, and the ability to regard them, in the moral sense, is analogous to different taste regions on the tongue. He spent considerable effort applying this to contemporary American politics. Liberals, he argues, value care far above all else, with fairness and liberty a strong but distinct second and third. Conservatives esteem care highly, but less than fairness and liberty. However the other three—loyalty, authority, and sanctity—are also highly valued by conservatives, but disregarded by self-described liberals. This leaves the liberal “moral sense” akin to being able to taste only sugar.
4) Esteem for sanctity, more than self-described conservatism, correlates in his research with some people’s “repugnance” at things that [allow me to interject] ought to be repugnant (though I don’t think he’d go that far).
5) Although the received wisdom is that contemporary bioethics is “autonomy on steroids” (my phrase, not his), as it were, IRB’s actually Invert the priority of the Belmont principles by making beneficience paramount. Top of the list of the IRB’s charge is to ensure that research risks to subjects are minimized and reasonable compared to the likely benefits. Informed consent is critical but comes after that. (Justice, in the form of equitable selection of subjects, may be third but is charging hard on the outside.) Note that there are no Belmont counterparts to loyalty, authority, or sanctity.
6) By a show of hands, about 40% of his audience was “liberal” and about a third of that number “conservative”—“the most conservative audience” he has spoken to.
It seems to me that Dr. Haidt really wants to be a moral realist and not an emotivist. But he appears not to allow that pre-rational commitments might be anything other than emotional. I am reminded of J. Budziszewski’s rejoinder that “naturalist” natural law fails; I prefer his appeal to “deep conscience” as the source of our moral intuitions (if I read him correctly). Also, Haidt’s “scientific” approach seems artificial to me (think: Postman’s Technopoly) and his categories thin alongside the biblical language of sin, righteousness, etc. (I couldn’t help also thinking of Paul Ricoeur’s The Symbolism of Evil.) But I want to read The Righteous Mind and I hope Dr. Haidt will have the chance to engage some conservative audiences.