Family and Twin Studies in Attention-Deficit Hyperactivity Disorder [chapter]

Christine Margarete Freitag, Wolfgang Retz
2009 Attention-Deficit Hyperactivity Disorder (ADHD) in Adults  
Twin and family studies in attention-deficit hyperactivity disorder (ADHD) did result in the findings of a strong heritable component (60-80%) of this disorder in children and adolescents. Twin studies have not yet been performed in adults. In addition to increased rates of ADHD in parents and siblings of children with ADHD, family studies resulted in a high risk for ADHD in the offspring of parents with ADHD implying strong familial, i.e. genetic or environmental risk factors in the adult
more » ... This corroborates findings from twin studies, which suggested that persistent ADHD might be an interesting phenotype for molecular genetic studies. The present review thoroughly presents findings from twin and family studies with regard to ADHD subtypes, sex differences, comorbidity rates, diagnostic aspects and environmental influences on ADHD. Besides persistent ADHD, ADHD with symptoms of conduct disorder or antisocial personality disorder might be another strongly genetically determined subtype, however family environmental risk factors have also been established for this pattern of comorbidity.
doi:10.1159/000258448 fatcat:yeaxujkra5gtjemsjia2y4wwmy