A 2018 study combined GWAS of intelligence and education to find 187 loci linked to general cognitive ability — a population-level statistical result, not an individual test, and specific to the European-ancestry cohorts studied.
Intelligence, in this genetic literature, means general cognitive function — performance summarized across several different cognitive tests into a single score, sometimes called g. Studying its genetics means asking why that score varies between people within a population, not judging anyone's worth or capability.
Hill et al. 2018 used a technique called MTAG (multi-trait analysis of GWAS) to combine a genome-wide association study of intelligence with a separate, genetically correlated GWAS of educational attainment — the two traits share a genetic correlation of 0.70, high enough that combining them raises statistical power without claiming they are the same thing. Doing this raised the effective sample size from 199,242 to 248,482 and found 187 independent genome-wide-significant loci, implicating 538 genes.
This method has a real limitation worth stating plainly: because MTAG borrows power from a correlated proxy trait, some of these 187 loci reflect genetic architecture shared between intelligence and educational attainment specifically, not necessarily intelligence considered on its own. The paper's authors built this analysis carefully and checked that it reproduced the pattern of genetic correlations seen in earlier intelligence-only studies — but the method's own logic means this list is not a pure isolate of "intelligence genes."
The paper's enrichment analyses found the associated genes concentrated in neurogenesis, myelination, genes expressed in the synapse, and genes involved in regulating the nervous system. Two variants on this page sit in genes matching those themes directly: rs56116382 sits in BSN (Bassoon), a structural scaffolding protein at the presynaptic terminal, and rs132570 sits in CACNA1I, a neuronal calcium channel subunit — concrete instances of the "synapse" and "nervous system regulation" categories the paper's own analysis names, not variants singled out for an unusually large effect.
With 187 loci across 538 genes, no single variant here does more than shift the population average by a very small amount. This is a highly polygenic trait in the fullest sense: the biology is real and distributed, and no one locus is a meaningful predictor on its own.
This is a European-ancestry finding. The paper's own quality-control steps explicitly removed UK Biobank participants without British ancestry, and its statistical calculations (linkage disequilibrium scores) used the European-ancestry reference panel from the 1000 Genomes Project. Like most large cognitive-genetics GWAS of this era, these results have not been validated in other ancestries and should not be assumed to generalize to them.
This page describes statistical variation within a population, not a test of anyone's intelligence. None of the 280 variants here predict an individual's cognitive ability, singly or combined — each explains a tiny fraction of population-level variance, and there is no genotype-based substitute for an actual cognitive assessment.
Two things this research does not do, stated directly because this literature has a history of being misused for exactly these claims: it does not compare groups or populations to each other, and it says nothing about differences between ancestries, countries, or any other group — the cohort studied was overwhelmingly one ancestry, which is precisely why cross-group claims cannot be drawn from it. What it does describe is genuine: measurable, replicated genetic correlates of a cognitive test score, varying between individuals within the population studied.
What a 23andMe/AncestryDNA export or raw VCF can and can't tell you about Intelligence comes down to these specific, well-studied positions — not a diagnosis. 303 positions are linked to this page; the ones this page's own text discusses are shown first.
The studies behind these variants recruited participants from different ancestries — a result found in one population doesn't always transfer to another. Based on 302 of 303 linked studies with a resolved discovery ancestry.
Databases, guidelines and references
General cognitive function — performance summarized across several different cognitive tests into a single score. The study asks why that score varies between people within a population, not how capable any individual is.
Using a method that combines genetically correlated traits (MTAG) to combine intelligence and educational attainment data, it raised the effective sample size to 248,482 and found 187 independent genome-wide-significant loci across 538 genes.
Partly, and the paper is explicit about this limitation: because the method borrows statistical power from a correlated trait, some of the 187 loci reflect genetic architecture shared with educational attainment specifically, not intelligence considered in isolation.
No individual variant does, and neither does the full set of 280 combined. Each explains only a tiny fraction of population-level variance — there is no genotype-based substitute for an actual cognitive assessment.
No. The study population was overwhelmingly one ancestry (British/European), which is exactly why no claim about differences between ancestries, countries, or other groups can be drawn from it. This page describes variation among individuals within the population studied, nothing more.
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