13 June, 2005

Standing in the way of progress

A concrete example of the detrimental effect of being caught in the coils of Christian fundamentalism:

A team of Korean* scientists under the leadership of Dr. Hwang Woo-Suk recently announced that they had successfully created 11 lines of stem cells from separate patients. The same team in 2003 announced that they had successfully cloned a human embryo by replacing an egg cell nucleus with a normal nucleus (which is necessary to prevent the recipient's immune system from rejecting the derived stem cell line).

This contentious announcement was immediately greeted by a flurry of disapproval, including by our own President, who said that he would veto any legislation devoted to expanding research into embryonic stem cells, and windy moralists harrumphing about the possibility of reproductive cloning.

It's unclear to me why reproductive cloning is being thrust into the therapeutic debate - we regularly develop technologies that simultaneously allow for great ill and great good (though I also fail to see why reproductive cloning is so horribly evil, as opposed to just terribly bizarre). We simply elect to avoid doing evil. We make such decisions every day; one doesn't demand that we stop the manufacture of scalpels simply because they can be used to slice open jugular veins.

And it's no more clear to me why religious people cling to the particular viewpoint that the zygote is a human being. This is certainly not a position with much Biblical justification, since not too long in the past (ca. 1700) the whole concept of fertilization was unknown, and we imagined that sperm were homunculi, "little men", that grew into a fetus when nurtured by the mother's womb.

The idea that the zygote contains a soul is similarly bizarre. Whence, then, the souls of monozygotic twins? Are there two souls inherent before the zygote splits? Or does a second arrive when the cells are cleaved apart? Does the soul, also, undergo a mitotic division in tandem with the zygote? And what of frozen embryos? Are their souls held in limbo? Isn't it a great crime to be imprisoning human souls indefinitely that way?

These sorts of thorny issues don't seem to confound any fundamentalist, however, and there remains a dogged insistence that we respect the sanctity of the human embryo. Thus, it is impossible in the U.S. to obtain federal funds to do the sort of research that Dr. Hwang is performing. One CAN obtain embryos and do research on them within the U.S. (and escape prosecution for murder) - but you have to get your embryos overseas and your research must be privately funded.

Juxtaposed against this is the use of adult stem cell lines, which many pro-lifers feel is a better ethical alternative. I had a near brush with this a few years back, when I came up as a match for a leukimia patient. Marrow donation is probably one of the most common and direct potential applications for stem cell research. It's a simple procedure: they draw serum from the donor, spin out their marrow stem cells (which periodically migrate into the blood and can be encouraged to do so via drugs), and inject them into the recipient's blood stream, where they will hopefully resettle into the marrow and begin producing blood cells.

This is one of the few instances where stem cells can be easily isolated, but it's also a clear instance where adult stem cell research won't suffice - there's no stem cell line to isolate and cultivate in the recipient at all because it's been killed by chemotherapy, which is why donation is required. Meanwhile the patient must languish for months in a sickly state, waiting, often in vain, for a suitable match to appear.

The sort of expertise that would allow us to convert embryonic stem cells into a viable marrow stem cell line is years away. It's absurd, however, that we preclude the very real and very exciting possibility of completely obsolescing marrow donor databases, simply because of an idiosyncratic and wholly unjustified belief about the nature and timing of the soul.

* South Koreans - North Koreans are caught in the grip of such dire poverty that it is impossible to imagine them accomplishing such feats. A recent survey of North Korean refugees found that the average height for teenagers was under five feet; the North Korean army had such difficulty recruiting soldiers that they had to revoke their minimum height requirement. The products of severe malnutrition and famine; food shortage remains a problem.

Self/non-self recognition remains one of the most awesome things the body does. At the centers of your lymphatic system are B-cells, which are trained to recognize only foreign proteins through via a simple culling mechanism. Every B-cell creates a unique receptor molecule through (essentially) a random process. When created, the cell has no idea what (if anything) this receptor will recognize. But it can test it against the range of proteins produced by the body (since, after all, every B-cell is equipped with a complete map of everything the body is capable of manufacturing). If its receptor is built to recognize an endogenous protein, the B-cell terminates itself. Thus, the library of surviving B-cells will be equipped to detect only foreign proteins - including transplanted tissue. Therefore, it's necessary that the derived stem cell line be genetically identical to the recipient. This is done by cultivating the cloned egg until it's reached the blastocyst stage (~1000 cells) and harvesting embryonic stem cells from it.

Dr. Hwang immediately shot back, "With all the great scientists and the great potential of the United States ... if because of some policy hurdle, the researchers cannot realize their dreams, I believe, as a fellow scientist this would be very regrettable."

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