Journal
BIOLOGICAL PSYCHIATRY
Volume 57, Issue 6, Pages 647-654Publisher
ELSEVIER SCIENCE INC
DOI: 10.1016/j.biopsych.2004.12.032
Keywords
attention deficit hyperactivity disorder (ADHD); twin study; genetics; longitudinal; early childhood; middle childhood
Categories
Ask authors/readers for more resources
Background: The high heritability of the core symptoms of attention-deficit/hyperactivity disorder (ADHD) has been repeatedly demonstrated, but few studies to date have investigated the extent to which the same genetic influences operate across development or new genes emerge at different developmental periods. Methods: We report data from a large, population-based study of approximately 4, 000 twin pairs, who have been followed up from early to middle childhood. Results: Parents' ratings of ADHD symptoms showed moderate stability across the ages, which was mainly due to shared genetic influences. There was also evidence of additional genetic influences, which were not shared with those acting earlier on, emerging at later age periods. The contribution of environmental influences to the stability of the ADHD symptoms over time was small. Parents' ratings on the Conners' DSM-IV ADHD subscale at the last assessment point, at an average age of 8 years, did not show the rater contrast effects that were observed in the parents' ratings at earlier ages with briefer measures. Similar estimates of genetic and environmental influences were obtained for girls and boys. Conclusions: We discuss the implications of the findings for molecular genetic studies on ADHD symptomatology.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available