Friday, December 12, 2008

Dignitas Personae: Theology and Stem Cell Research

The long-awaited Vatican Instruction, Dignitas Personae, was released today. It is a complex document that will require careful analysis. For instance, compared to Donum Vitae, does Dignitas assert that an embryo is a person from conception, something that Donum avoided asserting? Both agree, of course, that the embryo must be respected morally as a person from conception.

Two points stand out for me on my first reading. They concern Germline Modification and Altered Nuclear Transfer.

Regarding human germline modification, Dignitas is decidedly more negative compared to other recent Vatican statements. According to Dignitas, gene therapy that affects only the patient--"somatic cell gene therapy"--is acceptable. However,

The moral evaluation of germ line cell therapy is different. Whatever genetic modifications are effected on the germ cells of a person will be transmitted to any potential offspring. Because the risks connected to any genetic manipulation are considerable and as yet not fully controllable, in the present state of research, it is not morally permissible to act in a way that may cause possible harm to the resulting progeny. In the hypothesis of gene therapy on the embryo, it needs to be added that this only takes place in the context of in vitro fertilization and thus runs up against all the ethical objections to such procedures. For these reasons, therefore, it must be stated that, in its current state, germ line cell therapy in all its forms is morally illicit.

This rather bleak statement is in clear contrast to a previous Vatican statement entitled "Communion and Stewardship: Human Persons Created in the Image of God," which stated:

Germ line genetic engineering with a therapeutic goal in man would in itself be acceptable were it not for the fact that is it is hard to imagine how this could be achieved without disproportionate risks especially in the first experimental stage, such as the huge loss of embryos and the incidence of mishaps, and without the use of reproductive techniques. A possible alternative would be the use of gene therapy in the stem cells that produce a man’s sperm, whereby he can beget healthy offspring with his own seed by means of the conjugal act.

What is remarkable about the "Communion and Stewardship" text is that the statement actually suggested a way forward for research that could lead to a Vatican-approved approach to human germline modification. What is even more remarkable is that because of recent advances in stem cell research, especially induced pluripotency, research someday may actually achieve success in meeting the previously stated Vatican requirements. Now, however, Dignitas seems to back away from the previous endorsement. For more on this, see my recent book, Design and Destiny, from MIT Press.

The second issue has to do with "Altered Nuclear Transfer" (ANT), a provocative proposal that was seriously debated by the US President's Council on Bioethics. The idea, as championed by Bill Hurlbut, a member of the Council, was to create an "artifact" that might provide embryonic stem cells without being an embryo. The hope of the advocates of ANT was that those who oppose embryo research would see ANT as creating something that was decidely not an embryo and therefore an acceptable object for research. Now the Vatican has raised doubts:

These proposals [explicitly including ANT] have been met with questions of both a scientific and an ethical nature regarding above all the ontological status of the "product” obtained in this way. Until these doubts have been clarified, the statement of the Encyclical Evangelium vitae needs to be kept in mind: “what is at stake is so important that, from the standpoint of moral obligation, the mere probability that a human person is involved would suffice to justify an absolutely clear prohibition of any intervention aimed at killing a human embryo”.

If the Vatican has its doubts, then it's not clear who ANT is meant to placate. Sure, some individuals will say they oppose embryo research but find ANT acceptable. But the big institutional player, the Vatican, has just raised serious doubts and then asserted that doubt means no. As usual, the National Catholic Reporter provides a nice discussion of these issues, including quotes from Hurlbut.

Personally, I have never been a supporter of ANT, but I feel sorry for its advocates, who made the proposal in good faith in hopes that individuals and institutions would see it as a way around the difficult question of the use of the human embryo in research.

1 comment:

Ares said...

For an alternative to the use of gene therapy in stem cells that produce sperm of men, where she gave birth to offspring with the seed itself by conjugal act. This may reduce the pro-cons from the moral side. This study is yet to be continuously developed for the purpose of perfection. Well, this is valuable input for the theme of my blog somatic gene therapyof this a world of knowledge in medicine. Thank you.