Tuesday, March 08, 2005

"Is it alright to create and destroy something almost human?"

William Saletan discusses last Friday's meeting of the President's Council on Bioethics.
Council member Bill Hurlbut, a Stanford biologist, wants to end-run the moral debate over stem cells. He proposes to follow the recipe for human cloning—put the nucleus of a body cell into a gutted egg cell—but turn off a crucial gene so that the resulting 'biological artifact' produces stem cells without organizing itself into an embryo. According to a draft white paper prepared by council staff, 'Several scientists have indicated that they believe [the plan] can easily be made to work, and a few are apparently ready to try it out in non-human animals.'
The actual paper is here.
Using the techniques of somatic cell nuclear transfer (SCNT), but with the intentional alteration of the nucleus before transfer, we could construct a biological entity that, by design and from its very beginning, lacks the attributes and capacities of a human embryo. Studies with mice already provide evidence that such a project of Altered Nuclear Transfer (ANT) could generate functional ES cells from a system that is not an organism, but is biologically (and morally) more akin to the partial organic potential of a tissue or cell culture. …

[T]he proposed genetic alteration is accomplished ab initio, the entity is brought into existence with a genetic structure insufficient to generate a human embryo. From the beginning and at every point along its development it cannot be designated a living being. No human embryo would be created; hence, none would be violated, mutilated or destroyed in the process of stem cell harvesting.
Hurlbut make the following "moral argument."
The moral argument for Altered Nuclear Transfer is grounded in the emerging science of systems biology. According to this radical revision of our prevailing reductionistic views, an organism is a living whole, a dynamic network of interdependent and integrated parts.

There are essential subsystems of growth (cells, tissues and organs), but a living being is more than the sum of its parts, and the parts are dependent on the integrated unity of the whole. Fully constituted, the organism is a self-sustaining and harmonious whole, a unified being with an inherent principle of organization that orders and guides its continuity of growth. In the human embryo, this principle of organismal unity is an engaged and effective potential-in-process, an activated dynamic of development in the direction of the mature human form. Incompletely constituted or severed from the whole, subsystems with partial trajectories of development may temporarily proceed forward with a certain biological momentum. Ultimately, however, they fail to rise to the level of the coordinated coherence of a living organism and become merely disorganized cellular growth.

The activation of the egg by the penetration of the sperm (or the equivalent events in nuclear transfer/cloning) triggers the transition to active organismal existence. But without all of the essential elements (a full complement of chromosomes, proper chromatin configuration, the cytoplasmic factors for gene expression, etc.), there can be no living whole, no organism, and no human embryo. Recent scientific evidence suggests that such a 'failure of fertilization' is, in fact, the fate of most early natural initiations in reproduction. The artificial and intentional construction of a biological entity lacking any of these essential elements, yet bearing a partial developmental potential (similar to that in the aberrant products of fertilization), may make it possible to procure ES cells without producing a human embryo.
This is an essentialist argument that wants to differentiate a whole from its parts. I don't think it works. I am not opposed to embryonic stem cell research, but it seems to me that Hurlbut is attempting to make an argument for the sake of appeasing people who are not philosophically sophisticated enough to be appeased. He is saying that an embryo that is genetically incapable of developing into a human being should not be considered an embryo. Only embryos that have a genetic makeup sufficient for complete development should be considered human. Therefore, harvesting stem cells from his proposed "biological artifacts" violates no moral principles.

But certainly, we will eventually be able to do genetic surgery on artifacts such as these and allow them to develop properly. Then what? More generally, how does Hurlbut propose to draw the line? Which genes must be missing or mutated to disqualify a biological organism from being considered human? I doubt that this will be a line that can be drawn.

The real problem is that the anti-stem cell people believe in a soul, which as science progresses will require them to identify precisely when a mass of stuff gets a soul. That can't be done. Hurlbut is attempting to give them a way out—at least for now. I don't know whether they will take it or not, but it isn't a long term answer.

I also think that the people opposed to stem cell research on religious lines are taking a cowardly stance. It will not be easy to decide when abortion should be allowed. It will not be easy how to decide which biological entities deserve to be treated as human. By claiming that stem cell research is a religious (or "moral") issue those opposed are saying we don't have to think about these questions. Our religion or morality gives us a answer; we don't have to work it out for ourselves.

In my view, to take this stance is to fail to accept one's responsibility to look at issues as they arise and to make decisions when required. If one can say, "I don't have to think about it; a superior source tells me what the answer is." one is giving up one's essential humanity for the comfort of easy answers.

There are many difficult questions in life. We should be willing to face them all—and do so without falling back on an appeal to some externally given absolute answer. There aren't any.

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