Genetic research finally makes its way into the thinking of sociologists
If sociologists ignore genes, will other academics — and the wider world — ignore sociology?
Some in the discipline are telling their peers just that. With study after study finding that all sorts of personal characteristics are heritable — along with behaviors shaped by those characteristics — a see-no-gene perspective is obsolete.
Nor, these scholars argue, is it reasonable to concede that genes play some role but then to loftily assert that geneticists and the media overstate that role and to go on conducting studies as if genes did not exist. How, exactly, do genes shape human lives, interact with environmental forces, or get overpowered by those forces? “We do ourselves a disservice if we don’t engage in those arguments,” says Jason Schnittker, an associate professor of sociology at the University of Pennsylvania. “If we stay on the ropes, people from a different perspective, with a more extreme view, will be making them.”
Schnittker is among the contributors to a special issue of the American Journal of Sociology, the field’s flagship publication, devoted to “Genetics and Social Structure” — evidence that at least some sociologists are attempting to reckon with the genetic revolution. And not just in the AJS. Other top sociology journals, too, are publishing work incorporating genetic perspectives: The American Sociological Review in August published a much-discussed article on genes and delinquency by Guang Guo, of the University of North Carolina. (A couple of years ago, in an early foray on this front, Guo co-edited a special section of another top journal, Social Forces, titled “The Linking of Sociology and Biology.”)
It is even possible to identify sociology departments in which gene-environment interactions amount to a subfield: Chapel Hill, for one. Its department boasts at least five tenured scholars who write on the subject, and it offers a graduate seminar on genes and society.
The idea for the special issue of AJS was hatched a couple of years ago at Columbia University, under the aegis of that campus’s Robert Wood Johnson Health and Society Scholars Program. Its fellows are encouraged to reach across disciplinary lines, and Peter Bearman, who co-directs the Columbia program, found that he and two young visiting fellows, Brandeis’s Sara Shostak and Penn State’s Molly Martin, shared an interest in responding to the flood of new information about heredity. The three sociologists ended up editing the special issue.
“There was a sense,” Bearman says, “that there were two modes of thoughts about genetics and health. One was, ‘Genetics causes everything.’ Another was a refusal to think that anything related to genetic expression was worth studying.
“My view then, and my view now is that the embrace of genetic explanation and fear of genetic explanation were really the same phenomenon: an overemphasis on the role of genetics in shaping health outcomes.” In short, sociologists may shun genes because they secretly fear that genes are more powerful than they actually are.
To concede that some people are genetically encoded to have shorter fuses than others or are more likely to gain weight if granted unlimited access to Oreos is hardly to embrace a view of humans as lumbering robots ruled by genes, contributors to the AJS issue argue. Admitting as much is just the first step in a rich inquiry into the biological and social forces shaping human lives — an inquiry that sociologists, like few others, are equipped to make.
But even the most gung-ho genetically minded sociologists will say that their first baby steps toward consilience, E.O. Wilson’s term for the uniting of the biological and social sciences, don’t match that lofty rhetoric. In general the genetic sociological work is highly statistical, often involving relatively new multivariable techniques. It is devoid of the narrative description that sociologists who immerse themselves in their subjects’ lives can offer.
What has the work uncovered? In the AJS special issue, Schnittker rebuts the “set point” theory of happiness that has been espoused by some psychologists: the notion that there’s not much we can do about our innate levels of jubilance or melancholy. He makes use of a data set of people ages 25 to 75, including fraternal twins, identical twins, and nontwin siblings (looking at twins and nontwins helps isolate heritable characteristics), and finds that the environment does, in fact, matter — but in unpredictable ways. Marriage, he finds, has almost no effect on adult contentment once other factors have been accounted for. Friendships, on the other hand, matter a great deal — a reversal of sociologists’ usual ordering of these two sources of support. The explanation may be that we marry people who are much like us, while friendships are more random and labile, and thus more likely to bump us out of our habitual moods.
North Carolina’s Guo looks at a gene that has been tied to levels of dopamine, a neurotransmitter linked to aggressiveness and sexual energy. One variant of the gene, which may tamp down dopamine levels, has a “robust protective effect” against early first-time sex among teenagers, he finds. The protective effect vanishes, however, when teenagers with that genotype find themselves in schools where early sex is the norm. Meanwhile, Bernice Pescosolido, of Indiana University at Bloomington — who, like Guo, has several co-authors — finds that a version of the gene Gabra2, implicated by other researchers in an increased risk for alcoholism, has no effect on women. Even among men, those with the risky version have no increased risk for alcoholism provided they have strong family bonds.
The idea that social theorists must account for genes sounds commonsensical. But those doing the work, of course, labor under some dark shadows. Social science has a history of misguided, or worse, attempts to link genes to crime, or to deviance, or to IQ; racial differences have often been either a subtext of this work or the researchers’ main interest. Take your pick of flare-ups over the past 30 years: the reception of Crime and Human Nature (1985), written by the UCLA political scientist James Q. Wilson and the late Harvard psychologist Richard Herrnstein; comments, in 1992, by a National Institutes of Health official comparing inner cities to jungles and arguing that the breakdown of “social controls” in ghettos allowed genetic impulses to run free; a conference on crime and genes scheduled for 1992 and canceled after an uproar. (It was finally held in 1995.) Then, of course, there was the furor over The Bell Curve, in which Herrnstein and the political scientist Charles A. Murray, of the American Enterprise Institute, attributed social problems among racial minorities in part to low intelligence.
Sociologists spoke up during those controversies, but they have also criticized less obviously combustible genetic studies. Just two years ago, in his presidential address to the American Sociological Association, Troy Duster, an eminent sociologist at New York University, went so far as to suggest that any sociologist who embraced genetic approaches was a traitor to the discipline. Two of the biggest problems facing sociology, he argued, were the “increasing authority of reductionist science” and “the attendant expansion of databases on markers and processes ‘inside the body.’” If anything defined sociology, Duster said, it was its role as “century-long counterpoint” to such efforts to connect the roots of social problems to biology.
Duster recalled sitting on various governmental review boards and watching as what he considered an inordinate amount of money flowed toward geneticists and other scientists who studied maladies like alcoholism. Why spend millions searching for a predisposition to alcoholism among Native Americans, he asked, when their mistreatment and oppression offered explanation enough?
In an interview, Duster mostly affirms those remarks. “While in theory, one should embrace this theory of environmental-genetic research,” he says, “in actual practice, unless one is very, very sensitive to the stratification of the sciences, the table will be tilted in favor of genetics.”
Jeremy Freese, of Northwestern University, frames his contribution to the AJS special issue as a direct rebuttal of Duster. An oppositional stance makes sense “for some highly charged areas,” Freese grants, but it can’t be the whole agenda. He brandishes a list of 52 characteristics that have been found to be partially heritable: cognitive ability, extroversion, aggressiveness, likeliness to marry, age at first sexual intercourse, support for the death penalty, and on and on. Indeed, by now one should assume that “genetic differences are partial causes of the overwhelming majority of outcomes” that sociologists study. Nevertheless, he says, social scientists still engage in “tacit collusion” to ignore the role of genetic differences.
Nothing makes it easier on “imperializing” fields that already disrespect sociology, Freese writes — he mentions economics and behavioral genetics — “than an incisive, significant, and easily explained flaw shared by an entire literature.”
Ouch. Well, not an entire literature, not anymore. What has led to the new genetic turn in sociology, at least among a minority? In part it has to do with the availability of important new data sets. The National Longitudinal Study of Adolescent Health, aka Add Health, for example, at Chapel Hill, was designed from the start to incorporate both sociological and genetic information. It was begun, in 1994, by Bearman, J. Richard Udry, and Kathleen Mullan Harris. The idea was to capture as much information as possible about the social circumstances, friendship networks, and family conditions of 21,000 teenagers in 132 schools, from grades 7 through 12. The survey included a disproportionate number of twins, both fraternal and identical, full- and half-siblings, and adopted kids, allowing preliminary analyses of the heritability of traits. Follow-up interviews were conducted a year later.
Then, for the third wave of the study (in 2002), 2,500 siblings were asked for DNA samples (via cheek swabs). In wave four, now in progress and run by Harris, DNA is being sought for all participants (now they can just spit in a tube.) Many of the papers in the AJS issue draw on the Add Health study.
Improvements in genetic science have also given social scientists a firmer foundation on which to stand: Geneticists are getting much better at linking genes and groups of genes to illnesses and behavioral disorders.
Other social-science fields, too, have shown the way. The psychologist Avshalom Caspi, with appointments at the University of Wisconsin at Madison and King’s College London, has demonstrated that a gene associated with levels of the neurotransmitter serotonin can influence how resilient an individual is in the face of stressful life events. Caspi’s widely cited work is nuanced enough to win respect even from genetic skeptics.
It helps, too, that psychologists have turned up “progressive” results. One example is the finding, by the University of Virginia’s Eric Turkheimer, that IQ is far less heritable when a child’s parents are poor than when they are well off. That kind of stuff goes over well in sociology, a left-skewing field.
Guang Guo, of North Carolina, has thrown himself further than most sociologists into the genetic revolution. He began his career with an interest in statistics and in studies of twins, but as he moved toward an interest in genes he felt he had to retool. He has since enrolled in a half-dozen undergraduate and graduate courses on genetics.
For his AJS paper, on genetic influences on teenagers’ sexual activity, Guo zeroed in on several variations of a gene known as DAT1, which helps regulate levels of the neurotransmitter dopamine in the brain. In many species, including humans, high dopamine levels have been associated with sexual adventurousness.
Guo and his co-authors looked closely at 680 white males who had provided genetic samples to Add Health interviewers. (There were too few members of minority groups to adequately study.) The survey also provided information about, among other things, church attendance, whether the subjects had ever lived with a member of the opposite sex, their scores on an intelligence test, and an assessment of their physical maturity. Many of the purely “sociological” results were predictable: Young people who attended church weekly had 60 percent fewer sexual partners than their peers, for instance.
What was striking was the influence of a DAT1 variant known as 9R/9R (named for certain repetitive patterns in the bases that make up DNA), which was possessed by some 6 percent of the subjects. For those age 18 to 23, subjects with the 9R/9R variant had an average of 2.2 sexual partners, less than half the total reported by other men. And more of the 9R/9R men had never had sex. Moreover, they had higher grade-point averages, smoked and drank less, and buckled their seat belts more often.
Males with the 9R/9R genotype also reacted to their sociological surroundings in different ways. The 9R/9R “protective” element disappeared, sex-wise, once a high school hit the point where half the kids were sexually active at 16. And the 9R/9R males acted distinctively in other ways, too. Cognitive ability, for example, did not much affect the sexual behavior of the young men with the other genotypes. But for those with 9R/9R, there was a correlation: The “brightest” had the fewest sexual partners, the lowest-scoring on cognitive tests had the most.
Guo is quite cautious about drawing many conclusions from his findings. Replication is “a huge problem” in genetic studies, he says. Biomedical research has a long history of false alarms — of supposed genetic connections later debunked when larger groups of subjects underwent study. The new sociological studies risk repeating that history, because, so far, the databases that combine sociological and genetic information are quite small. That’s why Guo eagerly awaits the flood of new genetic information that wave four of Add Health will offer up.
Guo is even more cautious when discussing his August 2008 study of genes and delinquency. Delinquency, in that study, was measured according to information in the Add Health database about whether teenagers had, for example, ever stolen money, dealt drugs, or beaten someone up. Once again, the 9R/9R variant of DAT1 correlated with lower levels of socially frowned-upon activity.
Even more interesting was the way two other genes, DRD2 and MAOA, which also regulate neurotransmitters, appeared to interact with social conditions. If a young man had one variant of the MAOA gene, for example, repeating a grade had only a mild effect on his delinquency score. But if he had a different variant, one associated with higher levels of serotonin or dopamine, the delinquency score skyrocketed.
Guo controlled for race, so that the demographic makeup of his samples did not affect the findings, but he did not probe for racial differences. He knows that to do so “would be potentially explosive.” (And he knows “there are people waiting to jump on this,” mentioning by name J. Philippe Rushton, a Canadian psychologist who has made a career of documenting supposed racial differences.)
Guo has had a private detective visit him in his office to ask if he would test the detective’s clients, who faced the death penalty in a murder case, for the “delinquency gene,” in hopes that the result would make a judge and jury more sympathetic. Guo told the man to go away, as the research was preliminary.
In contrast to Guo, who has all but turned himself into a geneticist, Bernice Pescosolido is not shy about her relative ignorance of the science. She chose instead to team up with a genetic specialist, John I. Nurnberger Jr., a professor of psychiatry at Indiana University School of Medicine, who has studied the genetic origins of bipolar disorder and depression. Pescosolido sees herself as claiming new territory for sociology. Genetic sociology “is going to create an opportunity for social science to show how powerful the environment is,” she says.
Indeed, her team has found plenty of evidence of social forces driving people to drink. As income and education decrease, for instance, the risk of alcohol abuse goes up; as self-reported numbers of “daily hassles,” or reports of childhood deprivation, rise, so too does alcoholism. And while men who had the Gabra2 gene variant implicated in addiction had a 26 percent higher chance of being diagnosed with alcoholism, it was hardly guaranteed: Family ties could trump the genes.
Similarly, Penn State’s Molly Martin argues that incorporating genetic information can show that social influences are even more powerful than one might have thought. One example, on obesity, from a paper of hers in the AJS issue: Children who might be genetically predisposed to be chubby may find that propensity overruled by parents who aggressively discourage overeating. Or the tendency might be overruled if the family lives in a wealthy neighborhood with easy access to attractive parks and recreation. “The skeptics’ perspective all along,” she says, “has been that if genes do anything, they take away from the sociological story.” But, to the contrary, sociologists “might underestimate the social influences” by ignoring genes.
Not everyone, of course, is cheerleading the new movement. Duana Fullwiley, an assistant professor of medical anthropology and of African and African-American studies at Harvard, doesn’t find that Guo’s work on delinquency adds much to the picture that a geneticist would paint. Like a geneticist’s, Guo’s work is marred by “flat variables,” she says — factoids like how often a child shares meals with his family, or whether a student repeats a grade, replacing a fuller picture of a young life.
“I don’t think that these data sets let you have any kind of access to the processes these people were going through,” Fullwiley says. The new genetic sociology “is not doing what it claims to do.”
NYU’s Troy Duster adds that sociologists seem to be a step behind cutting-edge geneticists. Just as geneticists have begun to realize that genes act in concert in enormously complicated ways, and that DNA and RNA (which “reads” DNA) themselves interact in as yet unfathomable ways, sociologists are choosing to look at one gene at a time, and one trait at a time.
But Michael Shanahan, of North Carolina, another AJS contributor, replies that no social-science study can take account of every possible variable. His paper looks at the effect of a certain genotype on students’ continuing from high school into college. “If I had no genetic data at all, the study could be criticized for not taking into account all the social variables or environmental variables,” he says. “When you get into the genetic arena, the question becomes, Are there other genetic variables? And the answer is yes. But what we’re trying to do is pick variables that we think are decisive, for parsimonious reasons.” Incremental progress toward understanding is the hoped-for result.
The AJS issue is broad enough to include critics of the new approach. An article by Allan Horwitz, of Rutgers, and Brandeis’s Sara Shostak, takes what might be called a traditional sociological approach, discussing the social construction of depression and homosexuality. Whatever the genetic basis of those conditions, they explain, one has been intensely “medicalized,” while the other, thanks to the efforts of activists, is now largely considered to be part of normal human variation. In short, there is no truth “in the body.”
In an interview, Horwitz goes further, questioning an assumption that underpins several of the AJS articles. Contributors tip their hats to Chapel Hill’s J. Richard Udry, who theorized that genetic proclivities are freely expressed in the United States and other developed nations because social controls — such as bans on alcohol or intense disapproval of premarital sex — have largely fallen away. (Gabra2, the “alcoholism gene,” can’t express itself in Saudi Arabia, where alcohol is banned.) But that theory gives short shrift to the full diversity of human environments, Horwitz argues. What would the genetic studies show if conducted in modern Russia, ancient Rome, or 15th-century Mongolia? “The sweep of environmental variation is huge,” he says, yet the new studies capture just a tiny, Western corner of it.
Another critical sociologist, Ann Morning, an assistant professor at NYU, laments that race has reappeared in high-school biology textbooks, after an absence of a couple of decades, largely because of geneticists’ new interest in the concept.
But if nothing else, the debate is on. “Maybe the metaphor of the archive is the best one I can come up with,” says Columbia’s Peter Bearman. “What the discipline needs to understand is that there is this fabulously rich, potentially informative new archive out there, and we have to ask: How are we going to make use of that new information? How are we going to orient ourselves to that new data?”
Ignoring it isn’t an option. “The train,” says Molly Martin, “has already left the station.”
Christopher Shea, a former senior writer for The Chronicle, writes The Boston Globe’s Brainiac column.
http://chronicle.com Section: The Chronicle Review Volume 54, Issue 31, Page B6