DNA evidence for strong genetic stability and increasing heritability of intelligence from age 7 to 12.
Two genetic findings from twin research have far-reaching implications for understanding individual differences in the development of brain function as indexed by general cognitive ability (g, aka intelligence): (1) The same genes affect g throughout development, even though (2) heritability increases. It is now possible to test these hypotheses using DNA alone. From 1.7 million DNA markers and g scores at ages 7 and 12 on 2875 children, the DNA genetic correlation from age 7 to 12 was 0.73, highly similar to the genetic correlation of 0.75 estimated from 6702 pairs of twins from the same sample. DNA-estimated heritabilities increased from 0.26 at age 7 to 0.45 at age 12; twin-estimated heritabilities also increased from 0.35 to 0.48. These DNA results confirm the results of twin studies indicating strong genetic stability but increasing heritability for g, despite mean changes in brain structure and function from childhood to adolescence.
King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Denmark Hill, London, UK.
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M
Trzaskowski
University of Queensland Diamantina Institute, The University of Queensland, Princess Alexandra Hospital, Brisbane, Queensland, Australia.
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J
Yang
1] University of Queensland Diamantina Institute, The University of Queensland, Princess Alexandra Hospital, Brisbane, Queensland, Australia [2] Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia.
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PM
Visscher
King's College London, MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Denmark Hill, London, UK.
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Plomin
D000375:Aging / Q000235:genetics*; D002648:Child; D002657:Child Development; D005260:Female; D005819:Genetic Markers / Q000235:genetics*; D006801:Humans; D007360:Intelligence / Q000235:genetics*; D007361:Intelligence Tests; D008297:Male; D019655:Quantitative Trait, Heritable; D014427:Twins / Q000235:genetics
D005819:Genetic Markers