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:
Oof. Polygenic scores for IQ lose 75% of their explained variance when adding family controls, even worse than the attenuation for Educational Attainment. These are the scores Silicon Valley is using to select embryos 😬.
The TEDS cohort used here is a very large study with high-quality cognitive assessments collected over multiple time points. It is probably the most impressive twin study of IQ to date. That means very little room for data quality / measurement error issues.
It is important to highlight surprising null results. Just last week we were hypothesizing that large IQ score attenuation could be a study bias or an artifact of the Wilson Effect. Now we see it replicate in an independent study with adults.
Racism twitter has taken to arguing that observed racial differences must be "in part" explained by genetic differences, though they demure on how much. Not only is this claim aggressively misleading, it is completely unsupported by data. A 🧵:
Genetic differences between any two populations can go in *either* direction, matching the phenotypic differences we observe or going against them. Genes also interact with the environment, which makes the whole notion of "explaining" differences intractable.
The mere fact that a trait is heritable within populations tells us nothing about the explanatory factors between populations. See: Lewontin's thought experiment; Freddie de Boer's analogy to a "jumping contest"; or actual derivations (). pubmed.ncbi.nlm.nih.gov/38470926/
James Lee and @DamienMorris have an interesting perspective paper out describing "some far-reaching conclusions" about the genetics of intelligence. This type of "where are we now" paper is very fun and more people should write them! So, where are we now? 🧵
It's a short paper and it surveys three core findings from the past decade of intelligence genetics. These sections follow a structure that I would cheekily call ... "make a bold claim in the title, then walk it back in the text".
First up, they address the concern that associations with intelligence may actually be mediated by functionally irrelevant traits like physical appearance or pigment. The argument is that IQ GWAS has demonstrated enrichments for CNS/brain structure gene sets. This is true!
The SAT/meritocracy debate has always been a bit odd to me when the test makers themselves have studies showing self-reported high-school GPA is a consistently better predictor of college GPA and always adds on top of SATs.
Clearly SATs are neither the only nor even the best measure we have of college success and "holistic" admissions can be "meritocratic". It's up for debate whether the additional <10% predictive variance SATs give you are worth the high-school testing industrial complex.
A challenge with all of these analyses is they are measured after selection on the predictor variables themselves, which can induce biased estimates through range restriction. The raw correlations are even lower, and it is hard to know whether correcting is appropriate.
Hanania advocated passionately against "race mixing" for years, so he knows what he's talking about here. But it's worth adding that race-IQ obsessives also tend to make very poor predictions about the future. Let's review ...
The Bell Curve, published at the peak of the 80-90's crime wave, predicted a coming dystopian urban hellscape with a "cognitive underclass" living in state-managed facilities. Not only did all this fail to materialize, but crime rates collapsed.
Charles Murray has nevertheless spent the following 30 years predicting vindication for his claims was just around the corner ... each time pointing to a new corner.
Nice! Here we have an interesting paper using genetic ancestry to classify race/ethnicity in modern data and algorithms. Let's take a look at what this paper found: 🧵
First, I don't want to get too hung up on language, but TCB's tweet starts talking about "ethnicity", then shifts to "continental ancestries", and then entirely omits the largest ethnic group in the US: Hispanics. These terms have distinct definitions (). nap.nationalacademies.org/catalog/26902/…
Anyway, how well can this paper actually impute ethnicity from genetic ancestry in a large cancer population ()? ~17% of the time it gets Hispanic classification completely wrong or a no-call! worldscientific.com/doi/10.1142/97…