My genome is not my self
Posted by dlende on January 16, 2009
By Agustin Fuentes
We are not our genes and they are not us. Knowing what copies of genes we carry can tell us a little about getting sick and losing our hair, and maybe even add insight into our ancestry. But that does not tell us about how and why we do the things that we do.
Steven Pinker, in his recent New York Times Magazine article My Genome, My Self, argues that genes do have great influence on our behavior. As an anthropologist, evolutionary theorist, and a researcher of human and other primate behavior I am here to tell you that he is overshooting the mark. Human behavior is simultaneously biology, culture, experience and more.
Natural selection, one of the main drivers in evolutionary change, works on the whole body and behavior complex, not on single genes or even the genome itself. It is the dynamic product of genes, organs, bodies, behaviors, ecologies, and societies that eventually affects evolutionary patterns in humans. No gene or even set of genes can be held in isolation of the systems in which they exist.
Despite what Mr. Pinker says, current research has found no quantifiable causal links between gene products and intelligence, decisions to be “goth” or “jock”, and the drive for novelty. We do know that certain DNA strands are seen more commonly in some people with some behavior patterns than others, but never at 100% and rarely even half that. In nearly all of these cases we don’t even know what, if anything, those DNA strands (what genes actually are) do.
Each detailed example of gene impact that Pinker provides tells us nothing about behavior, but rather about the malfunctioning of some physiological system in our bodies. We understand the genetics of malfunction very well. From serious inheritable diseases to the inconveniences of baldness and tendency to grow hair everywhere but the head as we mature, we know many genetic influences on our physical function and malfunction.
But even these are influences, not determinates, and Pinker notes this. Although he tells us that “no one knows the non-genetic causes of individuality” and that knowing our personal genomics “will probably not change everything, or even most things” he steadfastly urges us to believe that our genes themselves are at least co-directors of our behavior, personalities, ideologies, and capabilities.
Why is this a problem? Genes matter, but so do many, many other things and none of them are truly independent of each other. Humans are extremely complex organisms, and our biology is always part of our daily lives, but so are social inequality and privilege, history, diet, stress, popular culture, activity patterns, familial pressures, etc…
To imply that we can possibly better know our true selves through a genetic test is as misleading as to state that we can do so via an IQ test, or an evaluation of our income, job, ethnicity, age, or gender. It is just not that simple, and the insistence that focusing on stretches of DNA will ever tell us who we are is an obstacle to the effective study of humans, one that has been fought against for nearly a century by anthropologists and biologists alike.
Mr. Pinker contributes significantly to the public discussion of what it means to be human and he does so eloquently. However, I urge all those readers who found his piece fascinating to move beyond the easy expectations that genetic tests will tell us much of anything about behavior. Read Nina Jablonski’s Skin, Jonathan Marks’ What Is Means To Be 98% Chimpanzee, or Anne Fausto-Sterling’s Sexing The Body and find out what we do and do not know about how our genes, bodies, biologies, and societies interact to create our amazingly rich and complicated selves.
Agustin Fuentes is Professor of Anthropology at the University of Notre Dame. He previously wrote Neuroanthropology and race – getting it straight. We have also featured a profile of his work on human evolution and niche construction and highlighted an interview he gave on myth busting and human nature.
In an inclusive spirit, we are featuring a wide range of reactions to Steven Pinker’s piece, some favorable, some critical.
Ars Psychiatrica, Who Are You?
Gene Expression, Personal genomics, Pinker, 23andMe, Counsyl, etc.
Genetic Future, The importance of confusion
John Hawks, Steve Pinker’s Hot Hot Legs profiled in NY Times Magazine
Mind Hacks, Personal genomics as a psychological mirror
Savage Minds, Are We Causality Crazy?
It is also illuminating to read the 33 reader comments to the article – again, quite a range of opinions.