<i>Also, what is your evidence that he&#x27;s not in touch with experts in psychometrics and human genomics? I don&#x27;t know him, but I have very much the contrary impression.</i><p>I don&#x27;t know him in person but I have emailed him. He is in touch with a lot of eminent experts (I know some of the same eminent experts and see some of the regularly in person), but he hasn&#x27;t imbued their worldview about human genetics, forged after years of pursuing other worldviews that don&#x27;t hold up to experimental test. But your comment is fair, so I&#x27;ll recommend here for you and for onlookers some writings by people who are experts in psychometrics and human behavior genetics.<p>The review article<p>Johnson, Wendy; Turkheimer, Eric; Gottesman, Irving I.; Bouchard Jr., Thomas (2009). Beyond Heritability: Twin Studies in Behavioral Research. Current Directions in Psychological Science, 18, 4, 217-220<p><a href="http:&#x2F;&#x2F;people.virginia.edu&#x2F;~ent3c&#x2F;papers2&#x2F;Articles%20for%20Online%20CV&#x2F;Johnson%20(2009).pdf" rel="nofollow">http:&#x2F;&#x2F;people.virginia.edu&#x2F;~ent3c&#x2F;papers2&#x2F;Articles%20for%20O...</a><p>includes the statement &quot;Moreover, even highly heritable traits can be strongly manipulated by the environment, so heritability has little if anything to do with controllability. For example, height is on the order of 90% heritable, yet North and South Koreans, who come from the same genetic background, presently differ in average height by a full 6 inches (Pak, 2004; Schwekendiek, 2008).&quot;<p>The review article<p>Johnson, W. (2010). Understanding the Genetics of Intelligence: Can Height Help? Can Corn Oil?. Current Directions in Psychological Science, 19(3), 177-182<p><a href="http:&#x2F;&#x2F;apsychoserver.psych.arizona.edu&#x2F;JJBAReprints&#x2F;PSYC621&#x2F;Johnson%20Current%20Directions%20Psych%20Science%202010%20(G%20and%20E%20in%20IQ).pdf" rel="nofollow">http:&#x2F;&#x2F;apsychoserver.psych.arizona.edu&#x2F;JJBAReprints&#x2F;PSYC621&#x2F;...</a><p>looks at some famous genetic experiments to show how little is explained by gene frequencies even in thoroughly studied populations defined by artificial selection.<p>&quot;Together, however, the developmental natures of GCA [general cognitive ability] and height, the likely influences of gene-environment correlations and interactions on their developmental processes, and the potential for genetic background and environmental circumstances to release previously unexpressed genetic variation suggest that very different combinations of genes may produce identical IQs or heights or levels of any other psychological trait. And the same genes may produce very different IQs and heights against different genetic backgrounds and in different environmental circumstances. This would be especially the case if height and GCA and other psychological traits are only single facets of multifaceted traits actually under more systematic genetic regulation, such as overall body size and balance between processing capacity and stimulus reactivity. Genetic influences on individual differences in psychological characteristics are real and important but are unlikely to be straightforward and deterministic. We will understand them best through investigation of their manifestation in biological and social developmental processes.&quot;<p>(The review by Johnson, by the way, is rather like Tao&#x27;s understanding of how mathematical talent develops in individuals, which prompted the blog post kindly submitted here.)<p>A comprehensive review article for social scientists on genetic research on IQ emphasizes what is still unknown.<p>Chabris, C. F., Hebert, B. M., Benjamin, D. J., Beauchamp, J., Cesarini, D., van der Loos, M., ... &amp; Laibson, D. (2012). Most reported genetic associations with general intelligence are probably false positives. Psychological science, 23(11), 1314-1323. DOI: 10.1177&#x2F;0956797611435528 <a href="http:&#x2F;&#x2F;www.ncbi.nlm.nih.gov&#x2F;pmc&#x2F;articles&#x2F;PMC3498585&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.ncbi.nlm.nih.gov&#x2F;pmc&#x2F;articles&#x2F;PMC3498585&#x2F;</a><p><a href="http:&#x2F;&#x2F;dash.harvard.edu&#x2F;bitstream&#x2F;handle&#x2F;1&#x2F;9938142&#x2F;Most_Reported_Genetic.pdf?sequence=1" rel="nofollow">http:&#x2F;&#x2F;dash.harvard.edu&#x2F;bitstream&#x2F;handle&#x2F;1&#x2F;9938142&#x2F;Most_Repo...</a><p>&quot;At the time most of the results we attempted to replicate were obtained, candidate-gene studies of complex traits were commonplace in medical genetics research. Such studies are now rarely published in leading journals. Our results add IQ to the list of phenotypes that must be approached with great caution when considering published molecular genetic associations. In our view, excitement over the value of behavioral and molecular genetic studies in the social sciences should be tempered—as it has been in the medical sciences—by an appreciation that, for complex phenotypes, individual common genetic variants of the sort assayed by SNP microarrays are likely to have very small effects. Associations of candidate genes with psychological traits and other traits studied in the social sciences should be viewed as tentative until they have been replicated in multiple large samples. Doing otherwise may hamper scientific progress by proliferating potentially false results, which may then influence the research agendas of scientists who do not appreciate that the associations they take as a starting point for their efforts may not be real. And the dissemination of false results to the public risks creating an incorrect perception about the state of knowledge in the field, especially the existence of genes described as being &#x27;for&#x27; traits on the basis of unintentionally inflated estimates of effect size and statistical significance.&quot;<p>The newer publications on the topic are not changing the picture significantly. If one desires to develop a child&#x27;s mathematical ability, for example (a problem I have pondered four times over as a parent), then the thing to do, after gaining whatever favorable shuffle of genes one can through thoughtful choice of a marriage partner, is to ensure that the child receives a sound primary education in mathematics. That is rarely done in the United States,[1] but it&#x27;s something parents can do if they know mathematics well through some other channel, for example having lived in another country.<p>[1] <a href="http:&#x2F;&#x2F;www.amazon.com&#x2F;Knowing-Teaching-Elementary-Mathematics-Understanding&#x2F;dp&#x2F;0415873843" rel="nofollow">http:&#x2F;&#x2F;www.amazon.com&#x2F;Knowing-Teaching-Elementary-Mathematic...</a><p><a href="http:&#x2F;&#x2F;www.aft.org&#x2F;sites&#x2F;default&#x2F;files&#x2F;periodicals&#x2F;amed1.pdf" rel="nofollow">http:&#x2F;&#x2F;www.aft.org&#x2F;sites&#x2F;default&#x2F;files&#x2F;periodicals&#x2F;amed1.pdf</a><p><a href="http:&#x2F;&#x2F;www.ams.org&#x2F;notices&#x2F;199908&#x2F;rev-howe.pdf" rel="nofollow">http:&#x2F;&#x2F;www.ams.org&#x2F;notices&#x2F;199908&#x2F;rev-howe.pdf</a><p><a href="http:&#x2F;&#x2F;www.math.wisc.edu&#x2F;~askey&#x2F;ask-gian.pdf" rel="nofollow">http:&#x2F;&#x2F;www.math.wisc.edu&#x2F;~askey&#x2F;ask-gian.pdf</a><p><a href="http:&#x2F;&#x2F;toomandre.com&#x2F;travel&#x2F;sweden05&#x2F;WP-SWEDEN-NEW.pdf" rel="nofollow">http:&#x2F;&#x2F;toomandre.com&#x2F;travel&#x2F;sweden05&#x2F;WP-SWEDEN-NEW.pdf</a><p><a href="http:&#x2F;&#x2F;educationnext.org&#x2F;when-the-best-is-mediocre&#x2F;" rel="nofollow">http:&#x2F;&#x2F;educationnext.org&#x2F;when-the-best-is-mediocre&#x2F;</a>