caa a22 4500 605476586 CHVBK 20210128100357.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s00787-014-0666-0 doi (NATIONALLICENCE)springer-10.1007/s00787-014-0666-0 Where are the strongest associations between autistic traits and traits of ADHD? evidence from a community-based twin study [Elektronische Daten] [Mark Taylor, Tony Charman, Angelica Ronald] Autism spectrum conditions (ASC) and attention-deficit/hyperactivity disorder (ADHD) regularly co-occur. Twin studies increasingly indicate that these conditions may have overlapping genetic causes. Less is known about the degree to which specific autistic traits relate to specific behaviours characteristic of ADHD. We hence tested, using the classical twin design, whether specific dimensional autistic traits, including social difficulties, communication atypicalities and repetitive behaviours, would display differential degrees of aetiological overlap with specific traits of ADHD, including hyperactivity/impulsivity and inattention. Parents of approximately 4,000 pairs of 12-year-old twins completed the Childhood Autism Spectrum Test and Conners' Parent Rating Scale. These measures were divided into subscales corresponding to different types of autistic and ADHD behaviours. Twin model fitting suggested that the degree of genetic overlap was particularly strong between communication difficulties and traits of ADHD (genetic correlations=.47−.51), while repetitive behaviours and social difficulties showed moderate (genetic correlations=.12−.33) and modest (.05−.11) genetic overlap respectively. Environmental overlap was low across all subscales (correlations=.01−.23). These patterns were also apparent at the extremes of the general population, with communication difficulties showing the highest genetic overlap with traits of ADHD. These findings indicate that molecular genetic studies seeking to uncover the shared genetic basis of ASC and ADHD would benefit from taking a symptom-specific approach. Furthermore, they could also help to explain why studies of the communication abilities of individuals with ASC and ADHD have produced overlapping findings. Springer-Verlag Berlin Heidelberg, 2015 Autism nationallicence ADHD nationallicence Twin study nationallicence Genetics nationallicence Comorbidity nationallicence Taylor Mark Genes Environment Lifespan Laboratory, Centre for Brain and Cognitive Development, Department of Psychological Science, Birkbeck, University of London, London, UK aut Charman Tony Department of Psychology, King's College London, London, UK aut Ronald Angelica Genes Environment Lifespan Laboratory, Centre for Brain and Cognitive Development, Department of Psychological Science, Birkbeck, University of London, London, UK aut European Child & Adolescent Psychiatry Springer Berlin Heidelberg 24/9(2015-09-01), 1129-1138 1018-8827 24:9<1129 2015 24 787 https://doi.org/10.1007/s00787-014-0666-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00787-014-0666-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Taylor Mark Genes Environment Lifespan Laboratory, Centre for Brain and Cognitive Development, Department of Psychological Science, Birkbeck, University of London, London, UK aut NATIONALLICENCE 700 1- Charman Tony Department of Psychology, King's College London, London, UK aut NATIONALLICENCE 700 1- Ronald Angelica Genes Environment Lifespan Laboratory, Centre for Brain and Cognitive Development, Department of Psychological Science, Birkbeck, University of London, London, UK aut NATIONALLICENCE 773 0- European Child & Adolescent Psychiatry Springer Berlin Heidelberg 24/9(2015-09-01), 1129-1138 1018-8827 24:9<1129 2015 24 787