Specific Abilities Heritable Beyond g

A mega meta‑analysis pooling 747,000 twin comparisons across 77 studies finds that multiple specific cognitive abilities (e.g., quantitative knowledge, reading/writing, processing speed) show substantial heritability that is not fully mediated by general intelligence. Several abilities exhibit age‑related increases in heritability, paralleling the pattern seen for g, and the data test whether gene effects sum linearly or interact. — This shifts intelligence debates from g‑only framings to a more granular genetic architecture that could reshape education policy, assessment design, and genomic research priorities.