ADHD, or attention deficit hyperactivity disorder, affects roughly 7 percent of school-age children in the United States. Kids with the condition have difficulty concentrating, act impulsively and tend to be overly active. ADHD has often been associated with other neurological conditions such as autism spectrum disorders, schizophrenia, bipolar disorder and learning disabilities. But until now, researchers have not been able to find the link between ADHD and other disorders.
A new study, published in Science Translational Medicine, has found that many different rare genetic variants are responsible for the condition. On top of that, some genes associated with ADHD have also been linked to other neurological disorders. Up to 75 percent of people with autism and autism spectrum disorders also have ADHD, but it was unclear whether or not these two conditions were genetically linked.
The new study looked at the DNA from parents of 173 of the children and found genetic variations — such as missing or copied genes — in the children who had ADHD and other neurological conditions.
“This really gives substance to the argument that there are shared genetic links between neuropsychiatric disorders, said lead researcher and child psychiatrist Russell Schachar of the Hospital for Sick Children.