Genetic Intelligence Tests Are Next to Worthless
Overview
NEW: Read popular science writer Carl Zimmer's article about Genetic Intelligence Tests (published on The Atlantic magazine, May 2018).
Human intelligence is highly difficult to quantify, and many tests have been developed to measure aspects of intelligence with varying degrees of success. However, studies have observed typically that individuals who do well on some tests tend to do well on others, and this positive correlation in scores has been called 'General' intelligence. 1
While intelligence has also been historically difficult to study from a genetic perspective 2, recently, a GWAS study of 78,000 individuals identified associations between 52 genes and intelligence 3, and was featured in the New York Times. We thought it might be interesting to base a report on these results although, like all genetic predictions, these predictions come with extensive caveats.
As the New York Times article points out, these genetic variants do not determine your intelligence. They contribute only a small fraction to explaining the variance in intelligence observed in the studied population (Europeans), and are likely to be involved in interactions between other genes and environmental factors in ways currently unknown. Errors are also compounded when applying predictions to other ancestry groups than the one studied. To reflect these issues, we report the polygenic score not as an absolute measurement, but as change in IQ based solely on these few genetic variants. These variants do not determine your overall IQ.
Lastly, of the 52 genes reported, only 18 were identified through SNP-based analysis, and a further 2 SNPs are not reported in our imputed SNP set. Your score is based on the 16 remaining SNPs.
Overview
NEW: Read popular science writer Carl Zimmer's article about Genetic Intelligence Tests (published on The Atlantic magazine, May 2018).
Human intelligence is highly difficult to quantify, and many tests have been developed to measure aspects of intelligence with varying degrees of success. However, studies have observed typically that individuals who do well on some tests tend to do well on others, and this positive correlation in scores has been called 'General' intelligence. 1
While intelligence has also been historically difficult to study from a genetic perspective 2, recently, a GWAS study of 78,000 individuals identified associations between 52 genes and intelligence 3, and was featured in the New York Times. We thought it might be interesting to base a report on these results although, like all genetic predictions, these predictions come with extensive caveats.
As the New York Times article points out, these genetic variants do not determine your intelligence. They contribute only a small fraction to explaining the variance in intelligence observed in the studied population (Europeans), and are likely to be involved in interactions between other genes and environmental factors in ways currently unknown. Errors are also compounded when applying predictions to other ancestry groups than the one studied. To reflect these issues, we report the polygenic score not as an absolute measurement, but as change in IQ based solely on these few genetic variants. These variants do not determine your overall IQ.
Lastly, of the 52 genes reported, only 18 were identified through SNP-based analysis, and a further 2 SNPs are not reported in our imputed SNP set. Your score is based on the 16 remaining SNPs.
