Scott Alexander, curated
← Back to curation

Missing Heritability: Much More Than You Wanted To Know

Quality
81
Excellent
Claude Shift
40
Moderate
RWI
3
of 10

Follow-up reading

Using AI To Research The Missing Heritability Post — re-checking the analysis with AI tools · Jul 2025

Highlights From The Comments On Missing Heritability — Highlights (companion) · Jul 2025

Summary

A deep, careful survey of the 2024-25 state of the 'missing heritability' debate: twin/adoption/pedigree studies put IQ/EA heritability at ~40-60%, but molecular methods (GWAS, GREML, polygenic scores) keep asymptoting near 15-20% (and only ~4-5% of EA validates as directly causal within families, per Tan 2024), fueling a new anti-hereditarian movement (Gusev, Turkheimer) that argues twin studies are 2-3x inflated. Scott patiently distinguishes predictive vs causal genes and the three confounders (population stratification, assortative mating, genetic nurture); explains why the newer Sib-Regression/RDR methods (which capture rare variants too) deepen rather than resolve the puzzle; then defends twin studies by walking through seven assumptions and showing each mostly holds, plus adoption/pedigree confirmation (and a vivid residency anecdote about adopted children of criminals). He concludes the twin/adoption estimates are probably right and the molecular methods likely miss rare variants/interactions, while flagging educational attainment as a 'cursed' sample-dependent construct and honestly listing the mysteries that remain. Scrupulous throughout: narrow- vs broad-sense heritability, credit to the anti-hereditarians, and a footnote on o3's hallucinations.

Why this score

Quality 81 · Excellent. Excellent band. A near-definitive-for-its-moment explainer of a genuinely hard, contested, technical literature, fairly representing the strongest opposing case and reaching a measured verdict, with first-rate expository devices (the racism-lactose confounding example; the genetic-engineer-vs-evolution Darwinian argument; the seven-assumptions walkthrough). Tied with the session's other top synthesis (the IABIED review, 81) and just below the standout Rootclaim writeup (84); held below the 85+ top-Excellent tier because it synthesizes rather than originates, and is deliberately inconclusive.

Claude’s paradigm shift 40 · Moderate. Moderate-low. The piece adjudicates an existing debate rather than introducing a new frame; its worth is clarity, fairness, and synthesis (scored in A), not publication-era novelty.

Real-world impact 3 · Moderate. A near-definitive-for-its-moment explainer of the hard, contested behavioral-genetics 'missing heritability' literature, fairly representing the strongest opposing case on a topic (IQ/heritability) with real social stakes. Influential at the level of understanding within a science-literate audience, but discourse-level with no material change — modest RWI.