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Results obtained from applications of heirarchical genetic models of intelligence provide some of the first evidence for gentic influences on specific cognitive abilities in childhood that are unrelated to those determining general cognition. Our results indicate that persistent infant genes are augmented by a novel genetic component that emerges at year 7 and continues to influence ability variation at year 9. The environmental outcomes indicate that although shared sibling environments do not exert a measurable effect in our sample, nonshared environmental factors play a large role in specific cognitive abilities.