ADHD and genetic syndromes.

A high rate of Attention Deficit/Hyperactivity Disorder (ADHD)-like characteristics has been reported in a wide variety of disorders including syndromes with known genetic causes. In this article, we review the genetic and the neurobiological links between ADHD symptoms and some genetic syndromes such as: Fragile X Syndrome, Neurofibromatosis 1, DiGeorge Syndrome, Tuberous Sclerosis Complex, Turner Syndrome, Williams Syndrome and Klinefelter Syndrome. Although each syndrome may arise from different genetic abnormalities with multiple molecular functions, the effects of these abnormalities may give rise to common effects downstream in the biological pathways or neural circuits, resulting in the presentation of ADHD symptoms. Early diagnosis of ADHD allows for earlier treatment, and has the potential for a better outcome in children with genetic syndromes.