The Doctrine of DNA: Biology as ideology
By R.C. Lewontin
Penguin Books. 128 pp. $14.95
Reviewed by Dave Riley
The definitive answer to how much you could drink and still feel good about it was recently supplied by the Sun Herald. "Alcoholism in the Genes" was a front-page story.
The newspaper outlined research which confirmed "widely held views" that there was a genetic cause of alcoholism. "This breakthrough", said the report, "follows the recent discovery of the so-called gay gene and a gene which causes breast cancer among women".
The secret of life is out: human personal and social attributes — like homosexuality and alcoholism — are caused by the physical make-up handed to us at conception. Science has spoken: we are trapped in a destiny confirmed before birth.
If some genes can cause cancer, maybe others conspire to make things bad for us. If there are genes for elbows, knees and toes, others must operate to form a human nature. Some genes good, some genes bad; we are stuck with it.
This all-encompassing and simplistic rationale is often presented as objective truth. If there is a line of causation which runs from gene to individual and then to society, the problems we confront in our lives must be universal and true for all time. Three billion years of evolution have made us what we are, so don't bother even to think of changing things.
Explanations such as these legitimise the society in which we live. If blacks are drunken or hubby comes home pissed again, don't go blaming our society for racism or unemployment; it does its best with the organic matter to hand.
Unfortunately, we all tend to be mesmerised by these "unassailable" facts. The claim that all human existence is controlled by our DNA is a popular one. Supposedly coded into our genes are differences in temperament, ability and physical and mental health. Transcending these ideas does not come easily. To believe that something better is both possible and necessary (and in itself, scientific) must be mere utopian dreaming.
Since most of us are not professional scientists, we cannot ourselves so easily prove otherwise. Maybe the competitive, entrepreneurial, and hierarchical social relations which differently reward different temperaments, cognitive abilities and mental attitudes are determined by DNA and are therefore unchangeable.
Fortunately, there are also scientists, like Richard Lewontin, who argue otherwise.
Lewontin is a leading geneticist and professor at Harvard University, where he holds the Alexander Agassiz chair in zoology. As the author of The genetic basis of evolutionary change and co-author of The dialectical biologist and Not in our genes, he readily identifies himself with a science dedicated to empowering people to be free.
The Doctrine of DNA is a little book which summarises in six chapters the arguments advanced in his previously published work. Through a concise and accessible polemic, originally delivered on Canadian radio, Lewontin advocates an alternative view to the increasingly orthodox claim that all human existence is controlled by DNA.
His message is that things are much more complicated and uncertain than such simple rules: "Development depends not only on the materials that have been inherited from parents — that is, the genes and other materials in the sperm and egg — but also on the particular temperature, humidity, nutrition, smells, sights and sounds (including what we call education) that impinge on the developing organism. Even if I knew the complete molecular specification of every gene in our organism, I could not predict what that organism would be ... [V]ariations among individuals within species are a unique consequence of both genes and the developmental environment in a constant interaction."
For those of us who locate ourselves on one side or other of the nature versus nurture divide, Lewontin is keen to dismantle such a division. For him, environmental and genetic variations are not independent causal pathways, nor are they separate in the sense that we usually view them. He opposes environmentalism — in genetics as well as in politics — because you cannot have one without the other. Organisms not only experience environments, they create them. Even during the life of an organism, its environment is constantly being remade.
So one of the most subtle of the arguments for biological determinism — that of partitioning the effects of environment and genes so that, for example, 80% of the difference between individuals is caused by genes and 20% by the environment — is dismissed by Lewontin. Under this scheme, manipulating the environment will not make much difference, when in fact a change in cultural environment, for instance, can change abilities by many orders of magnitude.
No-one insists that students should study without eyeglasses or that mathematics be performed using Roman numerals or without the aid of calculators. Differences between individuals are abolished by cultural and mechanical inventions such as these, just as gender-based variations in strength are irrelevant in a world of power hoists and power steering. In this sense there is no basic, unaided, naked ability that deserves our preoccupied interest. "The contrast between genetic and environment", he writes, "between nature and nurture, is not a contrast between fixed and changeable".
This may seem a bit messy to those used to an easy categorisation of the world into readily identifiable abstract entities, each with its own unique properties. Contrary to the orthodox philosophy of modern science, things are not separate from other things. The world described in The doctrine of DNA is not one in which parts are alienated from the whole or causes separated from effects. Nor is it indissoluble, its essence lost if we break anything down into its contributing parts.
This dynamic view in biology causes Lewontin to revise some of the major tenets of Darwinian theory. In doing so, he begins to uncover how working scientists can be so complicit in imposing an idealised human social model onto the natural world. The ideology of DNA, like that of Darwinism, reproduces nature not the way it is, but as it is viewed through the prism of our society.
Thus the contradiction of immense inequalities in a society that claims to be founded on equality is resolved by referring back to nature for a new gloss. Like a foot race, life must be measured by equality of opportunity rather than of result. Natural inequalities now find their true level because there are no artificial barriers to who gets what. An enlightened society such as ours enables individuals to attain their potential genetic capacity.
However, the unique interaction between the environment and the organism, says Lewontin, cannot be described as differences in capacity. "When the environment changes", he writes, "all bets are off".
Even the similarity between parents and their children is an observation requiring explanation. It is not evidence of genes. If 80% of Finns are Lutheran or three generations of the same Australian family vote Labor, no-one seriously argues that there is a gene for a specific religion and another for voting ALP.
Lewontin's measured claims about the complexity of life and how ignorant we are of what determines it are perhaps out of step with the scientific rhetoric we are used to. But such scepticism can save us from the compelling headlines that dramatise limited thinking. A succession of rather simplistic show-bizzed discoveries does not a human make.
While The Doctrine of DNA is a rigorous and unforgiving polemic, it is the breadth of Lewontin's vision that sustains its logic. This is radical science determined to harness an interpretation of both the natural and social worlds to help us to be free.
Who we are and what we might be are written neither in our stars nor in our genes. The science that makes and transforms us is not a rigid prescriptive biology but one "that can be understood and explored only through that unique form of experience, social action".