Significant genetic involvement in cognitive ability as measured by IQ has been demonstrated in several studies, but only a few studies have examined genetic influences on IQ during childhood development. We used a multivariate variance components method incorporating parametric correlation functions to model the heritability of IQ in healthy children aged 2 to 12 years, and the genetic and environmental correlations between serial measures of IQ across this age range. A total of 2,322 IQ scores (Stanford-Binet forms L and M) obtained between 1937 and 1961 from 370 white children in 139 families from the Fels Longitudinal Study were simultaneously analyzed. Represented in 305 of these individuals from 74 kindreds are 790 pairs of relatives ranging from monozygotic twins of 8th degree relations. The heritability of IQ was dynamic in the best fitting model, increasing monotonically from 69% at age 2 to 97% by age 12; the genetic correlation between serial IQ measures decayed monotonically to 0.63 between IQ at ages 2 and 12; and the environmental correlation between serial IQ measures decayed exponentially to zero. These findings suggest that there may be age-specific genetic influences on cognitive ability during childhood development.
|Original language||English (US)|
|Number of pages||1|
|Journal||American Journal of Medical Genetics - Neuropsychiatric Genetics|
|State||Published - Aug 7 2000|
ASJC Scopus subject areas
- Psychiatry and Mental health
- Cellular and Molecular Neuroscience