by Jonathon M. Sullivan MD, Ph.D.
EMBRYOS, FINGERNAIL CLIPPINGS AND HOMONCULI:
The Stem Cell Debate Rages On
In the latest issue of The New Republic (a most excellent journal of news, editorials and reviews that you should all subscribe to at once), columnist Andrew Sullivan mounts an eloquent but deeply flawed and reactionary argument against the continued federal funding of stem cell research ("Only Human," July 30, 2001). The Quantum Butcher read it. Then he read it again. He thought about it awhile. And then, he took up his particle cleaver.
I've always viewed QM as an educational column, and in general I don't use it for editorializing. Nevertheless, on this occasion I'm going to do just that, because this issue is so important and so divisive, because the technology involved is so replete with promise and peril, and because Mr. Andrew Sullivan is so irretrievably wrong, that the whole mess just begs to be on the cutting board.
Sullivan begins his argument by appealing to his audience's deep and abiding love...for Steven Spielberg movies. Recounting the grisly "Flesh Fairs" in the recent release Artificial Intelligence, in which Spielberg portrays the destruction of robots for the lurid entertainment of humans, Sullivan asks: "if robots deserve dignity, shouldn't blastocysts?"
Sullivan knows just how specious this comparison is, and asks the rhetorical question, "Is the analogy a stretch?" But instead of finding a creative way to extricate himself from his corner, Sullivan just stomps across the paint, portraying his comparison as having something to do with the old argument over whether a blastocyst is a human being. He hopes we won't notice that he's just compared the use of stem cells for the treatment of some of the world's most devastating diseases to sick thrills in a coliseum. But all of his handwaving can't disguise this cheap rhetorical trick.
So have it your way, Andrew. Let's pick that old scab of an argument. Is a blastocyst a human being?
Sullivan now proceeds to skewer himself neatly and then pretends it's only a flesh wound. He points out that, as far as most scientists are concerned, a blastocyst is "no more human than, say, a clipped fingernail (which contains all the DNA information for an entire person, just as accurately as a blastocyst)."
Sullivan thinks he's setting up a straw man, but in fact he has just made what is perhaps the single most compelling argument in favor of ignoring those who, like him, have a bizarre, unnatural fetish for little undifferentiated globs of protoplasm that just happen to possess hominid DNA.
So the debate's already over. His leg's off!
No it's not! "It remains a fact," Sullivan says, "that the embryo contains exactly the same amount of genetic information as you or I."
Except that is not a fact. It is clearly wrong.
You and I contain much, much more information, both genetic and otherwise, than a blastocyst. That's why I can write this column and you can read it, whereas a blastocyst just.. .sits there. Indeed, that is the exactly the point of stem cell research: the stem cells in the blastocyst have not yet acquired the molecular programming required for differentiation, and so they remain pluripotent, awaiting the necessary molecular signals (the information) that will tell them whether to become nerve or muscle, skin or bone.
Yes, once upon a time we were blastocysts, too. Nothing more than a little clump of cells, each of them a snippet of DNA surrounded by cytoplasm. But that DNA was later transcribed into RNA, and that RNA was translated into proteins. And some of those proteins were transcription factors that told other cells in the blastocyst what to do, when to divide, where to migrate. Transcription factors regulated the expression of still other transcription factors. Genes were turned on and off with clockwork precision. Some genes were methylated, so they could never be turned on again.
In other words, the genome and the proteome of the blastocyst were changed as the embryo accumulated molecular information that the blastocyst did not have.
The embryo became a fetus, with complex orientations of tissues--loaded with spatial, genetic, biochemical and mechanical information that simply did not exist in the embryo.
The fetus became a child with a nervous system, and that nervous system sucked up information about the world, hard-wiring pathways for vision and movement, learning to make subtle distinctions between this and that, accumulating information that simply did not exist in the fetus.
In other words, the blastocyst launched a genetic program that both extracted and acquired information. It didn't start out as a human being. It became a human being, with a personality, feelings, attitudes and memories, by accumulating information that was not there before.
Equating a blastocyst with a human being is like equating a brand new copy of an inexpensive spreadsheet program with the priceless databases that you'll eventually build up with that program. It's no less ridiculous than saying that a blueprint has the same value as a skyscraper--that it is the skycraper.
No. They are not the same.
But Sullivan's cellular fetish is implacable. "Once a blastocyst is killed, the human being coiled inexorably inside is no more." This remark is instantly evocative of medieval renditions of gamete structure in which little homonculi--fully-formed babies--sit curled up within the head of a spermatozoan, waiting to hatch. It's an illuminating image, because it reveals the archaic attitudes and intellectual dishonesty behind the argument that Sullivan and the reactionary fundamentalists have trotted out against stem cell research. Their starting point isn't the science of human biology, or the technology of stem cells, or the human needs that drive these endeavours. Rather, they embark from the dogmatic assumption that these little cells have been given a soul, a little baby-shaped spirit, at the moment of conception. If you accept this spiritualist model of the human, informed by Western religious mythologies, then a conscientious objection to anything that threatens the little homonculus-soul is reasonable. But Sullivan and other conservative intellectuals would rather not admit the religious foundations of their objection to a promising new form of medicine, because that might might render any decision to block federal funding vulnerable to a well-deserved charge of unconstitutionality. Instead they attempt to twist ill-digested readings of molecular biology to their purposes.
So let's give Sullivan a little more rope. We can certainly grant that a blastocyst and a fingernail contain the same genes. However, in 2001 we can no longer agree with his assertion that a fingernail can never become a baby. Clearly, it is quite within our grasp now to create a blastocyst from almost any cell of the body. Your hair follicles contain thousands--no, millions of potential human lives. Every cell in your body (save the erythrocytes) contains a nucleus, and that nucleus could be extracted and processed, and it could be placed in an enucleated oocyte, and you could implant that oocyte in a woman whose endometrium might be at the right stage for implantation, and that woman might carry the pregnancy to term.
And so two of Sullivan's three criteria for what constitutes a human being--viability and possession of a human genome--have just been extended to nearly every cell in your body, by virtue of the very sort of biology that created the stem cell debate in the first place.
So, when we use a depilatory, or take a skin graft, or pull a tooth, or masturbate, or use a condom, we are, by Sullivan's logic, "treat(ing) human life purely instrumentally. I know of no better description of evil."
That's right--we're evil when we clip a toneail. We're discarding thousands of cells which each have the capacity to become human beings, simply because it suits us to do so.
"Wait a minute," the fundamentalists object. "It's not the same. It would take focused application of technology to render those discarded cells into humans." But that is also exactly the case with blastocysts. Make no mistake--stem cells for research needn't be ripped from some woman's womb. It's probably better, scientifically and medically, if they aren't. Eventually, this technology will be used to produce tissues which are perfect genetic matches for the patient--because they'll have been produced from the patient's own cloned cells. Maybe even his fingernails. The zygotes will be produced in vitro and stem cells harvested from the resulting blastocysts. Blastocysts which might become human beings--with just a little less help from technology than would be required to make your fingernail a human being.
And so Sullivan's distinction between my nail clippings and the blastocyst that might be cloned from them falls apart.
Both his legs are off.
No they aren't, Sullivan says.
And we should expect him to say that, because although he's fought hard to make his fatally flawed argument that fingernails aren't human beings while blastocysts are, this distinction was always beside the point.
The point is the reactionary attitude, commonly found in the mouthings of religious fundamentalists and social conservatives, that all forms of human life are equally sacred and deserving of protection. And so we have no more right to murder a blastocyst than to murder Andrew Sullivan. It's a slippery slope, he tells us. No matter how you define human life--viability in the womb, possession of human genomic DNA, or the ability to be aware and suffer (Sullivan's third criterion), once you use that definition to excuse experimentation on blastocysts, Mengele-like atrocities on fully-formed and defenseless humans are sure to follow. We have to regard all manifestations of human life as precious. And that includes primitive dollops of goo like zygotes and blastocysts. Because, you see, they all have that little soul homonculus coiled up inside them. The Bible tells us so.
Of course, nobody does a better job of giving the lie to that argument than conservatives themselves. Every time he scrawled his name at the bottom of a death warrant, the former Governor of Texas made it quite clear that all human lives are not equally sacred and deserving of protection. The conservative agenda takes it as bedrock that babies are more precious than murderers.
I might be inclined to agree. The problem I have is that Sullivan and the hard-right social conservatives seem to think that undifferentiated blastocysts are more precious than a 42 year-old mother with multiple sclerosis, or a child with retinoblastoma, or a grandfather with congestive heart failure. Like the Black Knight bleeding all over the bridge to the twenty-first century, Sullivan refuses to admit that, despite all his protestations to the contrary, he is engaging in a moral calculus that values one end of the human developmental spectrum over the other.
And so am I. I'll put moms with MS, teenagers with cancer, and Mr. Andrew Sullivan ahead of an ameba in a petri dish, any day of the week.
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