The relationship between ADHD and key cognitive phenotypes is not mediated by shared familial effects with IQ

• DOI: 10.1017/s003329171000108x
• Publication Date: 2010-06-04T04:02:34Z
• Authors: A. C. Wood; F. Rijsdijk; K. A. Johnson; P. Andreou; B. Albrecht; A. Arias-Vasquez; J. K. Buitelaar; G. McLoughlin; N. N. J. Rommelse; J. A. Sergeant; E. J. S. Sonuga-B...; H. Uebel; J. J. van der Meere; T. Banaschewski; M. Gill; I. Manor; A. Miranda; F. Mulas; R. D. Oades; H. Roeyers; A. Rothenberger; H. C. Steinhausen; S. V. Faraone; P. Asherson; J. Kuntsi
• Keywords: Association (psychology); Family aggregation

Background Twin and sibling studies have identified specific cognitive phenotypes that may mediate the association between genes clinical symptoms of attention deficit hyperactivity disorder (ADHD). ADHD is also associated with lower IQ scores. We aimed to investigate whether familial measures performance diagnosis mediated through shared influences IQ. Method Multivariate models were run on data from 1265 individuals aged 6–18 years, comprising 920 participants pairs 345 control participants. Cognitive assessments included a four-choice reaction time (RT) task, go/no-go choice–delay task an assessment. The analyses focused variables mean RT (MRT), variability (RTV), commission errors (CE), omission (OE) choice impulsivity (CI). Results Significant ( r F) was confirmed both F=0.41–0.71) F=−0.25 −0.49). largely independent (80–87%) any contribution etiological factors exception for CI, where 49% overlap could be accounted by variance underlying Conclusions aetiological in seem distinct those RT/error measures. This suggests does not account key impairments observed ADHD. results implications molecular genetic designed identify involved