The stability of educational achievement across school years is largely explained by genetic factors

a Twin model-fitting results for univariate analyses of educational achievement. A？=？additive genetic, C？=？shared environmental, E？=？non-shared environmental proportions of the variance. b SNP heritability estimates of the proportion of variance explained by the additive effects of common SNPs (standard errors as error bars) for the same measures of educational achievement. SNP heritabilities were calculated following adjustment for sex and population stratification. Note: KS1 age 7; KS2 age 11; KS3 age 14; GCSE age 16; Note: Achievement is a composite score of English and Mathematic