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.
MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, United Kingdom. j.kuntsi@iop.kcl.ac.uk