Genetics may impact how long you stay in school—by a factor of a month or so. Photo by velkr0. Late update: Michelle Meyer, who sits on the advisory board of the consortium responsible for the study discussed below, briefly discusses the results on her blog, and links to a Frequently Asked Questions document [PDF] meant to accompany the study, which makes some reasonable and sensible points about how best to understand the findings. A point I didn't emphasize originally is that the small effect size of the sites identified suggests that a lot of previous "sociological genetics" studies are now called into question—because their sample sizes were far too small to detect such subtle effects.
A few months ago, I
roundly thrashed a study that attempted to identify genes associated with educational achievement. It was, to put it mildly, shooting fish in a barrel: that paper was published in a journal that doesn't handle much (if any) genetics research, the sample size was small, the genetic data was sparse, the analysis applied to the genetic data didn't test for what the authors wanted to test for, and the authors ignored basic statistical practice when they interpreted the results.
This week, though, there's
a new study of the genetic basis for educational achievement that is the mirror-image opposite of the one I beat up: it's online ahead of print in
Science, it has a great big sample size of 101,069 participants
and a built-in "replication" sample of 25,490 more, it works with good genome-wide genetic data, and it looks to be both admirably careful in its statistical work and cautious in its conclusions—which is consistent with the inclusion, in the paper's lengthy author list, of some folks who know what they're talking about when it comes to
association genetics.
So, naturally, I wanted to write something about this study as a nice example of what's possible when genetic analysis is done right. Unfortunately, the actual results of the study don't give me much to discuss—because, for all its rigor and caution, it
doesn't find much in the way of genetic explanation for educational achievement.