The roots of human behavior? AAAS and The Hastings Center host a public meeting
Can we talk? A public conversation about behavioral genetics and society
As scientists sift through the newly sequenced human genome, hopes are high that they’ll turn up the basic components of disabling mental disorders. But, is there a flip side to finding a biological basis for human behavior? Might past abuses be repeated? And, what does all this mean for free will?
An upcoming public meeting, sponsored by the American Association for the Advancement of Science (AAAS) and The Hastings Center, will take stock of experts’ latest thinking on the relationship between our genes and our behavior.
Leading scientists, ethicists, legal scholars, patient advocates, and journalists will take the stage in "Can We Talk? A Public Conversation About Behavioral Genetics and Society," May 2-3, 2003, at AAAS, in Washington D.C.
After decades of debate over "nature vs. nurture," scientists now generally believe that genes do play at least some role in determining our behavior. Dissonance still exists, however, between this view of behavioral genetics and those found outside the scientific arena.
"Substantial misunderstandings continue to lurk behind ongoing controversies over behavioral genetics," says Steven Hyman, Harvard University Provost and Keynote Speaker at the meeting. "In fact, the nature vs. nurture debate has no relevance to current science. Instead, we recognize that patterns of thought, emotion, and behavior result from a very complex interplay of multiple gene, environmental factors, and chance."
Behavioral genetics has often gotten a bad rap, and not without reason. Around the turn of the last century, researchers in the United States and Great Britain sought inherited causes for all sorts of human characteristics, from a supposed propensity toward becoming naval officers (supposedly a genetic trait called thalassophilia, for "love of the sea."), to qualities like "pauperism" and "feeblemindedness."
Along with these investigations came the idea that undesirable traits could be bred out of a population, and the term "eugenics," based on the Greek for "good birth" emerged. The concept reached its most horrific extreme during the Holocaust.
More recently, searches for genetic underpinnings of alcoholism, intelligence, and personality traits have sparked controversy, over the scientific strength of the data and the studies’ perceived implications – e.g., that some individuals may be less accountable for their actions than others. These sensational studies tended to link a single gene with a certain trait.
It’s far more typical for behavioral geneticists to investigate whether certain traits are heritable, while generally accepting that they won’t find a single gene involved.
"It can’t be the case that there is a ‘a gene’ for, say, how much television you watch," says speaker Eric Turkheimer of the University of Virginia. "The only thing that makes sense biologically and statistically is that there are hundreds or even thousands of genes that add up to some kind of tendency to watch a lot of television, for example."
Turkheimer says that just because we accept the basic tenets of behavioral genetics doesn’t mean we must see our actions as exclusively genetically determined. The downside to this middle-of-the-road approach, however, is that it imposes a limit to how much we can glean from studying the behavior of various family members.
"In fact, we have very little ability to understand or pull apart how any of those individual genes contribute to television watching," he says.
Nor is identifying specific genes necessarily required for studying the causes of behavioral disorders, according to Hyman.
"We should really be focused on understanding mechanisms. If we pose questions as to what are the factors — including genes — that build the brain in such a way as to result in schizophrenia or autism, we must go far beyond identifying some quantitative contribution of genes," he says.
It’s also possible to reconcile behavioral genetics with philosophical views of free will, according to Gregory Kaebnick, editor of The Hastings Center Report.
Rather than considering the mind as completely separate from the body, philosophers these days are more likely to accept that all human actions are biologically determined, Kaebnick says. But, that doesn’t rule out free will.
"Here, all we mean by freedom is an ordinary, down to earth type of explanation. Someone is free, deliberating about their actions in a normal, healthy way, not under any sort of external constraint…This account of the freedom of will is completely consistent with everything that behavioral genetics might show us," Kaebnick says.
Lest behavioral geneticists and the lay public get too comfortable linking genes and behavior, Troy Duster of New York University has some precautionary points.
First, we should recognize that just because a trait is genetic doesn’t mean that we are powerless to intervene with corrective or ameliorative strategies.
"Just having the condition does not mean that you then give up. There’s a kind of myth in the general public that if it is genetic, it’s destiny," he says.
Second, just because a trait is genetic doesn’t mean that it can be precisely defined or that it’s expressed in identical ways from one person to the next.
Finally, Duster predicts that we’re going to be increasingly inclined to give up certain freedoms, for example providing the police with our DNA samples, in return for greater sense of security.
Turning to the courtroom, Harold Edgar of Columbia University predicts that the concepts of behavioral genetics may affect criminal litigation through the decisions of those who administer the law.
In these settings, judges, prosecutors, and defense counsel exercise make decisions such as whether to charge criminally, what to charge criminally, and how to sentence.
"Precisely because many of these decisions are made by discretion and are loosely controlled by rules, it is important that professionals and the public have an appropriate understanding of the significance of the findings and their limits," Edgar says.
Ultimately, scientists should get the word out to the public that the basis of human behavior is complex, according to Hyman.
"We should realize that a print out of one’s genome is not equivalent to fate with respect to behavior and behavioral disorders. It is only probabilistic information — that can be readily overinterpreted and misused," he says.
The meeting, which is funded by the National Institutes of Health, has grown out of a multi-year collaboration between AAAS and The Hastings Center. This effort will result in a variety of resources for lay and professional audiences, including an introduction on behavioral genetics for the general public, a special supplement of Hastings Center Report for professional audiences, a volume of essays for scholars, and a special feature at a AAAS web site (http://www.aaas.org/spp/bgenes/).
American Association for the Advancement of Science. April 2003.