Sasha Gusev Profile picture
Statistical geneticist | Associate Prof at @DanaFarber / @harvardmed / @DFCIPopSci | Blogging at https://t.co/4D7UObBNdd

Jan 29, 2024, 11 tweets

So this is pretty typical of the low-information content you get from the genetic racists. The majority of this post is just blather but there is one (1) specific claim about genetics: that the molecular genetic contribution to IQ keeps going up every year. This is false. A 🧵:

The first study in 2011 into the heritability of IQ using molecular genetic methods found moderately high estimates 40-51%. But this approach was flawed technically (estimator bounds and population structure) and conceptually (environmental confounding).

Fast forward to 2023, using hundreds of thousands of people from the UK Biobank, Williams et al. [] ran a battery of analyses to refine a high-quality IQ estimate. The heritability ... 0.20 (with very precise error). pubmed.ncbi.nlm.nih.gov/36378351/

But this doesn't address the conceptual issue of environmental confounding. For that, Howe et al. used a large-scale within-family analysis, which does a much better job of isolating the genetic component from shared environment. Their estimate of the heritability ... 0.14!

So we've gone from 51% to 20% to 14% as the field has learned how to apply these methods more precisely and address confounding. Researchers that raised concerns of environmental confounds and stratification were proven right, and it's unlikely that we've resolved all the issues.

This trend is even more extreme for Educational Attainment, an easier to study trait with more practical relevance. Initial studies had estimates of 22% heritability which decreased to ~15% as better methods and more representative cohorts were applied.

When Howe et al. finally employed a proper within-family analysis their estimate of the heritability was ... just 4% (with a tight error bound). That's right, the *entire* common genetic contribution to educational attainment, a major status-driving factor, is a rounding error.

So the technical point is flat out wrong. And this style of argument mirrors a general trend. Charles Murray has been promising that his views will be vindicated in "just five years" since 1994!

Steve Hsu has been arguing that a 60% accurate genetic predictor is just around the corner since 2011, and last year declared himself vindicated! (As we just saw, the GWAS heritability of IQ is <14%, it cannot possibly reach 60%)

The shell game they play is: (1) claim that there's *lots* of evidence out there; (2) present one or two sketchy correlations based on bad methods; (3) promise that the better results are just around the corner. In the real world, their position keeps losing. /fin

Sailer tends to disappear whenever he is addressed directly so I'm not hoping for a response. Maybe in a day we'll get another story about sports or movies. But here are a few more unaddressed errors in the whole race/genes/IQ/outcomes project:

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