The Genetics of Educational Attainment - More Pieces

As Educational Attainment can be influenced by factors other than intelligence, such as ability to pay attention and personality traits, so too can IQ, though much less so.  Psychologists can only allow so much flexibility with you on time before it begins to affect your score, and the proxies for IQ such as the SAT require sitting still and following directions. Even prior to sitting for a test, everything you have been learning in life, in school or out up to that point also depends on your attention skills. One would think this would have a massive effect, but that does not seem to be the case.  Those with poor attention learn to jump to conclusions, to guess.  Brighter children do that better.  Still, it does not have zero effect.

Side note on standardised tests as proxies for IQ.  One of the reasons we believe there is a g-factor in intelligence is because the cognitive subtests are so different. Logical sequencing is different from vocabulary is different from digit-span retention is different from social reasoning, yet people who do well on one tend to do well on all of them. The tests are often given, in fact, looking to see if there are specific areas that are impaired and dragging overall performance down. How then, can standardised tests of vocabulary analogies and mathematical reasoning, administered in a specific and unusual format, capture g, even if the types of questions vary somewhat in the subtests?  The easiest answer is that they do correlate to IQ tests.  You can chart the scores of people who have taken both and they give consistent results. There are exceptions to this.  While the correlations are high, they are not exact.  In all tests, they not only have ceilings, but each subtest also has a ceiling. If you get a maximum score on any subtest, you are in a high percentile. Yet the test will not pick up if you are even better than that.  In mass testing there is simply no need for it. The number of people who can repeat backward a digit span of 12 is small.  No one much cares if you could actually do 20 or are a rare savant who can do 100.  In specific fields of endeavor such rare unmeasured abilities might be important.

Back to the Gene Discovery paper referenced two posts ago. They did uncover about 1200 SNPs associated with EA, some positively, some negatively.

For example, they strongly implicate genes involved in almost all aspects of neuron-to-neuron communication.We found that a polygenic score derived from our results explains around 11% of the variance in educational attainment. We also report additional GWAS (Genome-Wide Association Studies) of three phenotypes that are highly genetically correlated with educational attainment: cognitive (test) performance (n = 257,841), self-reported math ability (n = 564,698) and hardest math class completed (n = 430,445). We identify 225, 618 and 365 lead SNPs, respectively. When we jointly analyze all four phenotypes using a recently developed method11, we found that the explanatory power of polygenic scores based on the resulting summary statistics increases, to 12% for educational attainment and 7–10% for cognitive performance.

Those may seem to be small numbers, but when one considers that these are hard genetic markers for the traits, no longer very debatable in a nature-nurture context, it's a big deal.  There aren't single Education genes, but there seem to be collections of genes near each other on the chromosome that slightly improve (or damage) processing, memory, or reaction time.

In the interview I was listening to they gave further links if you want to dig even more deeply: Boyle et al., An Expanded View of Complex Traits: From Polygenic to Omnigenic. and Camille Benbow Life Paths and Accomplishments of Mathematically Precocious Males and Females Four Decades Later. I have browsed the articles but not read them entirely, so don't ask. The second one is especially accessible.  I'm just a talented amateur here, who can point you to better places.