Continuity and change in preschool ADHD symptoms: longitudinal genetic analysis with contrast effects.
The genetic and environmental mediation of continuity and change in parent-reported ADHD symptoms were investigated in a cohort of over 6000 twin pairs at 2, 3 and 4 years of age. Genetic analyses of the cross-sectional data yielded heritability estimates of 0.78-0.81 at each age, with contrast effects. A common pathway model provided the best fit to the longitudinal data, indicating that genetic influences underlie 91% of the stable variance in ADHD symptomatology. In other words, what is stable for ADHD symptoms is largely genetic. Contrast effects acting in the same direction at different ages contributed to the observed continuity:longitudinal correlations were greater for dizygotic than monozygotic twins.
Price
Thomas S
TS
Wellcome Trust Centre for Human Genetics, University of Oxford, UK. tprice@well.ox.ac.uk
Simonoff
Emily
E
Asherson
Philip
P
Curran
Sarah
S
Kuntsi
Jonna
J
Waldman
Irwin
I
Plomin
Robert
R
D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics*; D002675:Child, Preschool; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004739:England; D006801:Humans; D008137:Longitudinal Studies; D008960:Models, Psychological; D002666:Psychology, Child; D018433:Twin Studies as Topic; D014852:Wales