OBJECTIVE: Attention deficit hyperactivity disorder (ADHD) is a common, complex and highly heritable disorder, characterised by inattentive, impulsive and overactive behaviour. Evidence for the heritability of ADHD measures in twin population samples has come from the analysis of total scores that combine inattentive and hyperactive-impulsive symptoms subscales. This study investigated, in a community sample, the aetiology of ADHD-like traits and the aetiological overlap between the two dimensions that define the ADHD disorder. MATERIALS AND METHODS: Parents of 6,222 approximately 8-year-old twin pairs from the Twins Early Development Study (TEDS) population sample completed the two subscales of the Conners' 18-item DSMIV checklist, a screening instrument for ADHD symptoms. RESULTS: Both subscales were highly heritable (hyperactive-impulsive: 88%; inattentive: 79%). Bivariate genetic modelling indicated substantial genetic overlap between the two components; however, there were significant independent genetic effects. CONCLUSIONS: These findings suggest that many genes associated with the hyperactivity-impulsivity dimension will also be associated with the inattentive dimension but that there is significant genetic heterogeneity as well. These results provide genetic support for combining the two behavioural dimensions that define ADHD, but also suggest that some symptom-specific genes will also be identified.
OBJECTIVE: Attention deficit hyperactivity disorder (ADHD) is a common, complex and highly heritable disorder, characterised by inattentive, impulsive and overactive behaviour. Evidence for the heritability of ADHD measures in twin population samples has come from the analysis of total scores that combine inattentive and hyperactive-impulsive symptoms subscales. This study investigated, in a community sample, the aetiology of ADHD-like traits and the aetiological overlap between the two dimensions that define the ADHD disorder. MATERIALS AND METHODS: Parents of 6,222 approximately 8-year-old twin pairs from the Twins Early Development Study (TEDS) population sample completed the two subscales of the Conners' 18-item DSMIV checklist, a screening instrument for ADHD symptoms. RESULTS: Both subscales were highly heritable (hyperactive-impulsive: 88%; inattentive: 79%). Bivariate genetic modelling indicated substantial genetic overlap between the two components; however, there were significant independent genetic effects. CONCLUSIONS: These findings suggest that many genes associated with the hyperactivity-impulsivity dimension will also be associated with the inattentive dimension but that there is significant genetic heterogeneity as well. These results provide genetic support for combining the two behavioural dimensions that define ADHD, but also suggest that some symptom-specific genes will also be identified.
Authors: R D Todd; E R Rasmussen; R J Neuman; W Reich; J J Hudziak; K K Bucholz; P A Madden; A Heath Journal: Am J Psychiatry Date: 2001-11 Impact factor: 18.112
Authors: S L Smalley; J J McGough; M Del'Homme; J NewDelman; E Gordon; T Kim; A Liu; J T McCracken Journal: J Am Acad Child Adolesc Psychiatry Date: 2000-09 Impact factor: 8.829
Authors: Naomi Lowe; Aiveen Kirley; Ziarih Hawi; Pak Sham; Harvey Wickham; Christopher J Kratochvil; Shelley D Smith; Saretta Y Lee; Florence Levy; Lindsey Kent; Fiona Middle; Luis A Rohde; Tatiana Roman; Eda Tahir; Yanke Yazgan; Philip Asherson; Jonathan Mill; Anita Thapar; Antony Payton; Richard D Todd; Timothy Stephens; Richard P Ebstein; Iris Manor; Cathy L Barr; Karen G Wigg; Richard J Sinke; Jan K Buitelaar; Susan L Smalley; Stan F Nelson; Joseph Biederman; Stephen V Faraone; Michael Gill Journal: Am J Hum Genet Date: 2004-01-19 Impact factor: 11.025
Authors: Erik R Rasmussen; Rosalind J Neuman; Andrew C Heath; Florence Levy; David A Hay; Richard D Todd Journal: J Child Psychol Psychiatry Date: 2004-03 Impact factor: 8.982
Authors: Tomasz Schneider; Nicholas Ilott; Giovana Brolese; Lisiane Bizarro; Philip J E Asherson; Ian P Stolerman Journal: Neuropsychopharmacology Date: 2011-02-02 Impact factor: 7.853
Authors: Ali Mazaheri; Catherine Fassbender; Sharon Coffey-Corina; Tadeus A Hartanto; Julie B Schweitzer; George R Mangun Journal: Biol Psychiatry Date: 2013-10-08 Impact factor: 13.382
Authors: Chun-Zi Peng; Julia D Grant; Andrew C Heath; Angela M Reiersen; Richard C Mulligan; Andrey P Anokhin Journal: Dev Psychopathol Date: 2015-11-27