title: A twin study of the genetics of high cognitive ability selected from 11,000 twin pairs in six studies from four countries.
abstract: Although much genetic research has addressed normal variation in intelligence, little is known about the etiology of high cognitive abilities. Using data from 11,000 twin pairs (age range = 6-71 years) from the genetics of high cognitive abilities consortium, we investigated the genetic and environmental etiologies of high general cognitive ability (g). Age-appropriate psychometric cognitive tests were administered to the twins and used to create g scores standardized within each study. Liability-threshold model fitting was used to estimate genetic and environmental parameters for the top 15% of the distribution of g. Genetic influence for high g was substantial (0.50, with a 95% confidence interval of 0.41-0.60). Shared environmental influences were moderate (0.28, 0.19-0.37). We conclude that genetic variation contributes substantially to high g in Australia, the Netherlands, the United Kingdom and the United States.
authors.affiliation: Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, UK.
authors.forename: Claire M A
authors.initials: CM
authors.lastname: Haworth
authors.forename: Margaret J
authors.initials: MJ
authors.lastname: Wright
authors.forename: Nicolas W
authors.initials: NW
authors.lastname: Martin
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Martin
authors.forename: Dorret I
authors.initials: DI
authors.lastname: Boomsma
authors.forename: Meike
authors.initials: M
authors.lastname: Bartels
authors.forename: Danielle
authors.initials: D
authors.lastname: Posthuma
authors.forename: Oliver S P
authors.initials: OS
authors.lastname: Davis
authors.forename: Angela M
authors.initials: AM
authors.lastname: Brant
authors.forename: Robin P
authors.initials: RP
authors.lastname: Corley
authors.forename: John K
authors.initials: JK
authors.lastname: Hewitt
authors.forename: William G
authors.initials: WG
authors.lastname: Iacono
authors.forename: Matthew
authors.initials: M
authors.lastname: McGue
authors.forename: Lee A
authors.initials: LA
authors.lastname: Thompson
authors.forename: Sara A
authors.initials: SA
authors.lastname: Hart
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Petrill
authors.forename: David
authors.initials: D
authors.lastname: Lubinski
authors.forename: Robert
authors.initials: R
authors.lastname: Plomin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001076:Aptitude; D001315:Australia; D002648:Child; D002672:Child, Gifted / Q000235:genetics*; D002675:Child, Preschool; D003431:Cross-Cultural Comparison; D005260:Female; D018740:Genetic Heterogeneity; D006801:Humans; D007360:Intelligence / Q000235:genetics*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D009426:Netherlands; D013223:Statistics as Topic; D014429:Twins, Dizygotic / Q000235:genetics*; D014430:Twins, Monozygotic / Q000235:genetics*; D006113:United Kingdom; D055815:Young Adult