Wednesday, May 11, 2016

Epigenetics as epiphenomenal

               There is an interesting intellectual war going on right now, between scientist/author Siddhartha Mukherjee and molecular geneticists.  It was precipitated by Mukherjee’s recent article in The New Yorker on the wonderful world of epigenetics.

               Geneticist Jerry Coyne  objected stridently to the New Yorker essay. Now, Coyne is one of those people who thinks that a real scientist should not be able to tell a human from an ape, and has chastised me in the past for being able to.  Such people are either deaf, dumb, and blind, or else they don’t think that the choice to privilege genetic relations (which make it hard to tell humans from apes) over ecological relations (where it is really, really easy to tell humans from apes) requires a justification.   In fact, in the 1960s, G. G. Simpson demanded such a justification, and never got one. Historians like Marianne Sommer, Joel Hagen, and Michael Dietrich have been writing about it.

               Mukherjee is responding to his critics.  Anyway, since I already knew that Coyne is apparently not very good at confronting his intellectual prejudices, I thought it might be a good time to reconsider just what is at stake intellectually in this epigenetics business. I talked about this a little in my Annual Review of Anthropology article a few years ago.  But actually it’s a nice example of how understanding the science can be helped by asking the lawyerly question “Cui bono?” (who benefits?).  And further, it helps to show that this isn’t a controversy of biology, but of biopolitics.

               Point #1: Human genetics is invariably biopolitical. To see this point, you must grapple with the history of human genetics.  Not the history as told by scientists, the time-line approach that begins, “Once upon a time there was Archibald Garrod...” – but the history as told by historians.  That’s the history that looks at what scientists said to the public, and at the associated social relations.  The twentieth century, after all, began with eugenics and ended with “genohype” – which no sensible geneticist wants to defend today.

               And we nearly span the century when we compare the concluding statement of the first textbook of Mendelism (1905) with the director of the Human Genome Project’s comment to Time Magazine in 1989. First, the eponymous Reginald C. Punnett, remembered in science today for his square:

“As our knowledge of heredity clears and the mists of superstition are dispelled, there grows upon us with an ever increasing and relentless force the conviction that the creature is not made but born.”

               Ummm, WTF?  Granted, genetics was important enough to him to write a book about, but the message that “the creature is not made but born” is certainly not its central message.  Its central message is about how the creature gets born – not that the facts of birth are the only important things about it.

               Compare James Watson: “We used to think our fate was in the stars.  Now we know, in large measure, our fate is in our genes.”

               Now, I know, throwing out Watson quotes is hardly even fun any more, and nobody in science really believes him.  But let me just remind you that he knows more about DNA than you do, and he has a fucking Nobel Prize.  What have you got?

               What these two thoughts have in common, 84 years and a whole lot of data and theory apart, is their biopolitics.  They are saying something very important, and it’s not about fruitflies, nor is it about the ABO blood group.  It’s about your lot in life.  It’s about who you are, and what you can aspire to become. And it’s a fairly pessimistic note, if your origins are humble: You can never transcend you ancestors. Read it:

The creature is not made, but born.
Our fate is in our genes.
Your personal development is strictly limited by your ancestry.

Now, that is a message that resonates far beyond genetics.  It is familiar to readers of 1994's The Bell Curve, for instance, whose authors were a psychologist and a political theorist.  It is there in the 19th century political writings of Arthur de Gobineau.  It is also familiar to readers of pre-modern geneticists, such as August Weismann and Francis Galton.
            What is interesting in the present context is the broad opposition to that pessimistic statement, and the alternative scientific venues for studying how the creature is indeed made, our fates are not in our genes, and we can become different from our ancestors.
              One such venue, which was popular in the late 19th and early 20th centuries, was the inheritance of acquired characteristics, often known as Lamarckism. This of course petered out with the suicide of Paul Kammerer in the 1920s, but has never been entirely buried. Bipedalism, after all, was a behavioral choice made by our ancestors, for which we no longer have a choice.

               Another venue for studying how we are made is culture, which eventually superseded eugenics as the favored mode of improving society in the 20th century.

               And still another is human adaptability.

               So over the course of the 20th century, we actually learned that, despite the biopolitical rhetoric of geneticists, there were in fact several significant ways in which you could become different from your ancestors and not necessarily be limited by them.

              The scientistic rhetoric turned once again with the Human Genome Project in the 1980s. To get that program off the ground, molecular geneticists groomed the public with sound-bites like James Watson’s.  Then (like the eugenicists of the 1920s) they embarked on a wildly successful public education program, to convince taxpayers that three billion dollars to sequence the human genome would be the best three billion dollars we ever spent.

               And a wave of purple scientific prose flowed in its wake.  Remember “Mapping the Code”?  That’s still my favorite mixed metaphor.  And “Mapping our Genes”? And “The Human Blueprint”? And “The Book of Man”?  How about “The Code of Codes”?  (I still don't know what that actually means, except that it is vaguely evocative of Jesus as "King of Kings," and of The Godfather, as "capo di tutti capi".)  Remember how the Human Genome Project was the most important scientific revolution since Galileo and we were going to know what it meant to be human and cure all genetic diseases and stuff?

               Ah well, the important thing is, they got the money.  So what if the public transiently believed that your DNA code was the most important thing about you? Hey, it's just a hypothesis.  And it might be true, right?
               Let’s now answer the question “Cui bono?”  Who benefits by having the educated public misbelieve that your DNA code is the most important thing about you?  Two principal groups – just as in the 1920s.  First off, the one percent – those now favored by nature, not merely by avarice or luck or unscrupulousness - and who are inclined to try and give their own kids a financial leg up in this dog-eat-dog world, rather than redistribute the wealth in the form of public goods and services that might permit others to compete more fairly in that world.

               And second, the molecular geneticists – the ones now studying the most important thing about you.  Your DNA code.  In fact, anything’s DNA code.  It’s also The Frog Blueprint and The Book of Frog.  That is Point #2: It is in the interests of the molecular geneticists to have you believe that everything important about you lies in the field of molecular genetics.

               That is a significant convergence of interests with the one percent.  Back to history.

              By the late 1930s, the developmental geneticist C. H. Waddington was distinguishing between the kind of information in a human cell that distinguishes one person from another (genetic) and the kind of information that distinguishes one cell type from another, with identical DNA sequences (epigenetic).  Waddington’s  reputation had been all but eclipsed in genetics, when Stephen Jay Gould revived him in evolutionary biology, specifically in the call for an evolutionary science of organismal form, rather than the reductive evolutionary science that was normative in the 1980s.

               Epigenetics is a label for the non-reductive study of heredity.  You are no longer just your ancestors’ DNA sequences, but also their methylation and transcriptional regulation patterns.  But more significantly, your genetics is far more conservative than your epigenetics.  Your “epigenome” is responsive to the environment; that is to say, it adapts.  And it does so far more rapidly and directly than your genome does.

               That extends our list of alternative scientific venues for studying your non-DNA-sequence-based self just a bit.  In addition to the study of possible Lamarckian inheritance, culture, and human adaptability, there is now epigenetics.  In other words, the significance of epigenetics lies in its biopolitical role as a reaction against the genetic determinism, or hereditarianism, that accompanied the Human Genome Project.

              There is, in fact, a lot more at stake than just transcription factors.  The smart geneticists already know that.

               Waddington, it turns out, was a very smart one.  He was a broad intellectual, and actually wrote a book about art at the end of his life.  I don’t think he was that big of a Marxist, as Mukherjee suggests, although he was certainly left of center politically, and was instrumental in getting the famous University of Edinburgh science studies program going (known as the “strong programme”).

              Waddington’s biology was also always very well-informed anthropologically.  When he and his wife visited New York they always stayed with Margaret Mead.  Why? Because Waddington’s BFF from college days at Cambridge was Mead’s third husband, Gregory Bateson.  (Waddington’s daughter is a distinguished Cambridge social anthropologist.)  The major influence on Bateson and on Waddington was not the philosopher Marx, but the philosopher Alfred North Whitehead, also very much the anti-reductionist, but a bit more spiritual.

               At least I think so.  He may have been less impenetrable in person. He’s fucking tough in print.  

               Gregory Bateson’s 1936 ethnography Naven acknowledges some influence of Waddington and Whitehead in a footnote.

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