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8 posts found
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Dec 03, 2025
acx
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13 min 1,961 words 590 comments 420 likes podcast (13 min)
Scott examines a new genetic study on missing heritability that both hereditarians and nurturists claim vindicates their position, concluding that despite the study's advances, the fundamental debate over how heritable traits like IQ actually are remains unresolved. Longer summary
This post discusses a new genetic study that attempted to resolve the "missing heritability" debate - the gap between high heritability estimates from twin studies (50-80%) and low estimates from molecular genetic studies (10-20%). The study used whole-genome sequencing to include rare genetic variants and found they could account for about 88% of expected heritability, but the actual heritability estimates themselves were only medium (30-40%). Both hereditarians and nurturists claimed victory: hereditarians because the gap was closed (proving the genes exist), nurturists because the total heritability found was still lower than twin studies suggested. Scott examines both sides' arguments, including measurement error corrections and various confounders, and concludes that despite everyone's claims, the debate remains fundamentally unresolved as different methods continue producing different estimates with no clear explanation why. Shorter summary
Sep 04, 2025
acx
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54 min 8,283 words 918 comments 233 likes podcast (45 min)
Scott Alexander presents his monthly collection of interesting links and developments across technology, science, culture, and policy, with personal commentary on each item. Longer summary
Scott Alexander shares a collection of 61 interesting links, spanning topics from AI development and scientific studies to cultural observations and policy discussions. The post covers diverse subjects including GPT-5's reception, genetic research, religious demographics, urban development, mental health studies, and various scientific discoveries. Scott provides commentary and analysis on many of these items, often connecting them to broader themes or offering his perspective on controversial issues. Shorter summary
Jul 31, 2025
acx
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56 min 8,637 words 748 comments 407 likes podcast (60 min)
Scott analyzes the sudden emergence of commercial trait-based embryo selection services, discussing both the scientific validity and ethical implications of selecting embryos for health outcomes, intelligence, and physical traits. Longer summary
Scott examines the recent development of commercial embryo selection services, particularly focusing on companies like Genomic Prediction, Orchid Health, Nucleus, and Herasight. He explains how the technology works, comparing different companies' claims and methodologies, and discusses both scientific challenges and ethical concerns. The post explores the potential benefits, like reduced disease risk and increased IQ, while acknowledging issues around cost, racial disparities, and social implications. A significant portion focuses on Herasight's critique of competitor Nucleus's scientific claims. The post concludes by placing this technology in the broader context of human enhancement and future technological developments. Shorter summary
Jul 03, 2025
acx
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66 min 10,199 words 134 comments 94 likes podcast (61 min)
Scott Alexander responds to comments and criticism on his earlier post about 'Missing Heritability', discussing issues like gene-environment interactions, sequencing technology limitations, and the use of polygenic scores across ancestry groups. Longer summary
This post compiles and responds to notable comments on Scott's earlier post about 'Missing Heritability'. The post is structured in four sections, starting with responses from experts named in the original post, particularly Sasha Gusev who critiques the treatment of gene-environment interactions and cross-population polygenic scores. The second section features detailed technical comments from knowledgeable readers about topics like genetic interactions and sequencing technology limitations. The third section addresses specific corrections to the original post, while the final section covers various other interesting comments and discussions. Throughout, Scott engages with the criticisms and new perspectives while maintaining his original position on most key points. Shorter summary
Jun 26, 2025
acx
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68 min 10,491 words 669 comments 456 likes podcast (62 min)
Scott explores the 'missing heritability' problem in genetics, where twin studies show traits like IQ and educational attainment are highly heritable but newer genomic methods find much lower heritability, analyzing various potential explanations for this discrepancy. Longer summary
The post examines the 'missing heritability' problem in genetics, where twin studies consistently show behavioral traits like IQ and educational attainment are substantially heritable (around 40-60%), while newer genomic methods find much lower heritability (around 15-20%). Scott reviews the history of behavioral genetics research, explains various study methodologies and their potential biases, and analyzes different hypotheses for this discrepancy. He examines whether twin studies might be flawed, whether newer methods might be missing important genetic effects, and whether educational attainment might be an unusually problematic trait to study. While acknowledging remaining mysteries, he tentatively concludes that twin studies are probably largely correct and that newer methods may be missing rare variants and genetic interactions. Shorter summary
Nov 01, 2024
acx
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42 min 6,373 words 932 comments 216 likes podcast (41 min)
A diverse collection of news items, studies, and interesting facts from November 2024, covering topics from scientific discoveries to cultural phenomena. Longer summary
This post is a compilation of various news items, studies, and interesting facts from November 2024. It covers a wide range of topics including scientific discoveries, political events, technological advancements, cultural phenomena, and historical anecdotes. The post is structured as a numbered list, with each item briefly summarizing a piece of news or information. Some notable items include a new schizophrenia drug approval, YouGov polling results on various historical figures, findings on genetic IQ changes over time, and updates on AI technology and its implications. Shorter summary
Sep 12, 2024
acx
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32 min 4,892 words 990 comments 215 likes podcast (29 min)
A compilation of 50 diverse news items and links from September 2024, covering topics from politics and economics to science and technology. Longer summary
This post is a compilation of 50 diverse links and news items from September 2024. It covers a wide range of topics including politics, science, technology, economics, and social issues. Some notable items include discussions on kidney donation compensation, personality genetics, fertility rates in Israel, drug decriminalization in Oregon, AI regulation in California, and various political and economic analyses. The post also includes commentary on recent studies, books, and social phenomena. Shorter summary
Jul 24, 2024
acx
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21 min 3,173 words 934 comments 180 likes podcast (20 min)
Scott Alexander presents a diverse collection of 41 links and news items, covering topics from science and politics to history and technology, with brief commentaries and insights. Longer summary
This post is a collection of 41 diverse links and news items covering a wide range of topics. The items include scientific studies, political developments, historical anecdotes, technological advancements, and cultural phenomena. Scott Alexander presents these with brief commentaries, often adding his own insights or expressing skepticism about certain claims. The tone is informative and occasionally humorous, with Scott pointing out interesting connections or implications of the information presented. Shorter summary
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