Replicable genetic variants influencing school, and IQ

The social science genetics consortium has been working to uncover the genes associated with educational attainment. First, in 2013, with 127,000 subjects, they were able to produce a polygenic risk score (PRS) explaining 2% variance in total years of education.
This doubled to 4% once they had convinced collaborators to contribute data from 329,000 subjects in a great paper by Okbay et al. reported on by The Atlantic as well as in Nature :-).
Comfortingly, this PRS replicated in the open UKBiobank sample of 100,000 adults.
Now grad-student Saskia Selzam¬†working in the TEDS group reports in Molecular Psychiatry (along talks at BGA and our own ISIR conference) that in a sample of twins which is much smaller (5,825 adolescents), but which has actual school grades rather than the much cruder “years of education” yard stick, this EA2 score (as it’s known to insiders) accounts for 9% of differences in age-16 school grades or 15% of the heritable variance. Interestingly, this is three times what was accounted of general cognitive ability. EA2 GPS also accounted for 7% of family socioeconomic status.
The EA2 PRS is going to be an invaluable tool both for testing claims about how to improve school, and in giving us insight into why some people learn better in the current system.