Education Reads to Start Your Week, June 15th

Advances in Genetics, A Decade of Bad Genetics, Environmental Impacts on Brain Structure, Bonus 4th Link

Author

James Shanahan
June 15, 2026

Hi! This is Scholastic Alchemy, a twice-weekly blog where I write about education and related topics. Wednesday posts are typically a deep dive into an education topic of my choosing and Mondays usually see me posting a selection of education links and some commentary about each. If Scholastic Alchemy had a thesis, I suppose it would go a little like this: We keep trying to induce educational gold from lead and it keeps not working but we keep on trying. My goal here is to talk about curriculum, instruction, policy, public opinion, and other topics in order to explain why I think we keep failing to produce this magical educational gold. If you find that at all interesting, please consider a paid subscription here, or at the parallel publishing spot on Beehiiv. (Some folks hate the ‘stack, I get it.) That said, all posts are going to remain free for the foreseeable future. Thanks for reading!

Advances in Genetics Research

I feel like the contrarian and edgy take vis-a-vis schools in recent years is to chalk everything up to biology and argue schools just don’t do much. Dumb kids are dumb because they have bad genes or they come from “bad” cultures or some other highly deterministic thing that can be blamed on whole groups of people. It seems this is less true than proponents of strong genetic impacts would have us believe. Eric Turkheimer discusses some of the new methods we have to evaluate the impacts of genetics, namely Genomic Relatedness Matched Association (GRMA). GRMA gives us the ability to improve on twin studies and on Genome-Wide Associate Studies by evaluating the genetic differences within families. Turkheimer reports that studies based on these newer methodologies show an even smaller impact of genetics on educational attainment (a proxy measure for intelligence) than previous studies based on prior methods. Namely, polygenic scores — the PGS in the quote below, it refers to a measure of heritability — are more weakly related to educational attainment than previously thought.

The purported meiotic randomized trial instantiated by the PGS accounts for one tenth of one percent of the variance in EA. (Maybe the squared beta is better here, I’m not sure, but none of those reach 1% either.) I have harped on this before, I don’t need to do it again, but it is truly amazing: the authors don’t even remark on their own finding. All of the genomic enthusiasm for the first four versions of EA — the steadily increasing effect sizes, the gene finding, the biological annotation, the practical applications— has been washed down the drain, and no one seems to care enough to note its passing.

Two-hundred years later, it turns out Grandma Galton was right. The default naive hypothesis is true, and that is all there is. High MZ twin correlations, SNP hits for behavior, statistically significant results for PGS: none of them are evidence that the world has turned out to be any more genetic than Galton’s Grandma thought; they are no more than what the Default Naive Hypothesis looks like when examined through different methodological lenses. It’s all just normal, squishy, uncontrolled human development. Genes and environment both “make a difference” for educational attainment in some general and unsatisfying way, but all attempts to identify either one as causal main effects wind up reducing them to zero.

You should really read the whole thing, if only to get an explanation for all the acronyms and what-not. Grandma Galton’s “naive hypothesis” that turned out to be right was that people’s “organic constitution” and being “born into different family circumstances” are mixed together in uncertain ways that are impossible to disentangle. We have to assume that both matter and that we can’t know which matters most for either an individual or for a group.

A Decade of Bad Genetics Research

Meanwhile, last year Sasha Guesv explained that because of GWAS, we had to put up with a decade of bad genetics findings that she calls “sensationally false” because of population stratification. Population stratification is “the apparent association between genetic variants and the trait of interest that have no true direct causal effect” and it’s caused by a combination of a population structure that results in the non-random distribution of alleles and environmental differences that act as a confounding variable.

how much of a problem is population stratification in real GWAS? Turns out it can be a big deal, often even overwhelming the actual trait-influencing variation. And it is a particularly big deal for precisely the traits you might imagine: those that are related to education and socioeconomic status and thus under strong social stratification.

From what Guesv writes, it really looks like a lot of studies from the mid 2000s to 2019 were not accounting for population stratification. Worse still, it led some researchers down dark, eugenics adjacent pathways that continue to haunt discussions of, for example, educational attainment.

But prior to learning this error, the possibility of selection on head circumference got people speculating what else about the head could be under rapid recent selection. That speculation included an famous opinion piece by esteemed population geneticist David Reich raising concern that genetic analyses may soon reveal substantial biological differences among human populations on traits like intelligence; differences that we as a society were unprepared to grapple with1. Naturally, in some circles, Reich’s cautious and circumscribed warnings that we may eventually find challenging genetic differences were read as a kind of Straussian message, a cryptic admission of precisely the “racist prejudices and agendas” Reich was attempting to head off (and, I should note, that he spent another two chapters in his book explicitly denouncing). Snippets from his editorial were further stripped of context, sometimes reworded entirely, and became meme fodder for open racists: Harvard’s superstar geneticist is secretly on our side, the truth about the inferior races will soon be revealed. And these memes continue to get passed around today, more than five years since the motivating height result was shown to be an artifact (in a paper on which Reich is a corresponding author no less). All of which is to say that poor control for population structure can have, well, some pretty big consequences.

So, not only did a decade or more of bad genetics research get us a resurgence in scientific racism, it also may be why so many people insist that the only thing that really matters in school is the kids’ genetic inheritance. The corollary there is that more money, better curriculum, air conditioning, etc. Genes are all that matters, they say, so nothing else is worth the effort.

Environmental Impacts on Brain Structure

Speaking of environmental confounders, they also shows up in things like brain structures. Marek and colleagues bring novel geographic and socioeconomic analyses to brain-wide association studies to show that the environmental impact of a low-SES neighborhood on brain structures outweighs other common explanations like differences in IQ or psychopathology. Notably, they are able to pick out a few specific causes for brain differences.

Socioeconomic circumstances are more powerfully associated with brain function and structure than other variables. The dominant socioeconomic brain pattern matches the known effects of sleep deprivation and stress (primary motor and sensory) while sparing higher-order cognitive regions in the frontal and parietal cortices. Thus, it appears most likely that environmental factors indexed by neighborhood socioeconomic status, including sleep and stress, strongly shape childhood brain organization. This stands in contrast to brain-IQ associations that are confounded and reflect shortcut learning of socioeconomics rather than brain-based differences. Accounting for socioeconomics improves BWAS interpretation and generalizability. In summary, neighborhood socioeconomics represent the principal axis shaping brain organization during childhood and beyond, potentially through sleep and stress.

At this point, anything that’s getting the [something] Wide Association Study label is getting downgraded in trustworthiness for me. I think, though, the overall point of these three links should be clear. We can’t know accurately for either individuals or groups whether genetics or environment have a greater impact on things like educational achievement. People telling us that they can tell and who want us to design policy based on expectations drawn from genetics are wrong and are drawing on flawed research. Moreover, other aspects of children’s physiological growth and development, like their brains, are imparted by environmental conditions, perhaps more so than previously thought. Something like a lack of sleep or facing acute stress creates differences in brain structure and function with clear implications for educational attainment.

Since we’re an education blog, let’s bring this kind of thinking more directly to bear on an education topic: Gifted and Talented. Writing for New York magazine, Katie Arnold-Ratliff wonders if the entire idea of giftedness is a lie.

Some parents I spoke to have already washed their hands of the whole G&T business, refusing to participate in what they view as a corrupt system But countless others still place significant stock in the G&T designation and what it offers and are comfortable relying on cognitive testing, should it be required, to determine whether a child qualifies. For decades, people in favor of G&T have promoted the notion that we can put a concrete number to a child’s intelligence, that the smartest children need extra enrichment or acceleration to reach their potential, and that we can measure the beneficial impact of that enhanced learning on the children who receive it.

There is just one problem: Not a single part of this story is true.

I’ll leave the article to you to read and instead focus on just one point. The logic that underpins intelligence and cognitive testing in schools is the same logic that Gusev identifies as “meme fodder for open racists.” These tests are designed to find differences in groups and separate them out to receive “better” instruction and more resources. We don’t frame them this way and we don’t openly acknowledge that a certain kind of segregation is one of the main selling points of G&T. Meanwhile, in both genetics and other aspects of human biological research, we’re learning that “nature’s” role is not so predominant that we should ignore environment. The systems and social structures that we build inside schools and out will play a major role shaping kids environment and in their growth and development. Let’s not discount that because we’re stuck in Bell Curve thinking.

Thanks for reading!