The Chronicle of Higher Education has a long article about the tentative pairing of genetics and sociology. The occasion for the article is a recent issue of the American Journal of Sociology that features studies that combine genetics with sociology in various ways. Some are finding interesting things:
North Carolina's [Guang] 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 theme of the article:
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.
Social scientists described in the article yearn to discover that things are "nuanced" or show hidden dependencies to environmental factors. Fair enough -- if you study hammers, why not look for nails? Still, it gets boring to find that every case ends with that "stinger" that shows how environment is the most important thing after all. Heritability is a ratio: If it's nonzero and nonunity, you'll have both environmental and genetic variance.
And some take skepticism to an extreme:
[Troy] 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?
Oh, hey, why spend millions "searching" for a predisposition to Type 2 diabetes, when you know that overeating is explanation enough? That "searching" thing? Some of us like to call that "understanding"! As in, when you understand something, maybe you could do something about it!
Well, it's a long article with a number of references to different research connecting genetics and behavior. Many of the examples have to do with adolescent behavior, because they draw upon the National Longitudinal Study of Adolescent Health, which was designed to examine heritability of various traits.
I think the most important potential of behavioral genetics is to let us understand the normal range of variation of behavior. The examples that look at the different reactions of genetically similar individuals in different environments are very interesting, and certainly confirm the importance of environments in such behaviors. But if we want to understand society, we need to understand how genetically different people tend to behave (or feel) differently in similar environments.
