Study Raises Possibility that ADHD is Genetic

By Susan Brady

Study Raises Possibility that ADHD is Genetic

It was in 1902 that physician George F. Still first documented what is now known as attention deficit/hyperactivity disorder (ADHD), and despite more than a century of research, its exact cause is still not fully understood. Evidence to date indicates that there are many underlying factors that lead to the inattention, impulsiveness and hyperactivity seen in ADHD, among them genetic and neurobiological vulnerabilities. New research by a group of international researchers believe they have direct evidence that points to a genetic abnormality as a component of ADHD.

The team, based out of Cardiff University in Wales, has identified a significant excess of large, rare copy number variants (CNVs) in children with ADHD compared with control participants. The average number of CNVs was 2.09 times higher in children with ADHD. This type of CNV has been found to contribute to neurodevelopmental disorders including intellectual disability, schizophrenia, and autism. This led researchers to conduct a genome-wide analysis of 306 children who had been diagnosed with ADHD, but who did not have schizophrenia or autism. Their results were replicated from an independent dataset of 825 Icelandic patients with ADHD from deCODE Genetics.

"Our first aim was to examine whether children with ADHD had an increased burden of CNVs compared with controls and to test whether this increase was attributable to associated intellectual disability since ADHD, similarly to autism and schizophrenia, occurs with increased frequency in individuals with intellectual disability," the researchers explained. "Our second aim was to investigate whether identified CNVs in our ADHD sample were significantly enriched for a specific chromosomal locus or loci previously implicated in autism and schizophrenia."

ADHD is the most commonly diagnosed childhood psychiatric disorder, estimated to affect three to seven percent of America’s children. On average, at least one child in every classroom in the United States needs help for the disorder. However, more than half of ADHD children will continue to display characteristics of the disorder throughout adolescence and adulthood. This research points strongly to the possibility that genetics plays at least a part in some, if not all, ADHD cases. This will help dispel the notion that ADHD has only a social causation, stemming from the home environment.

Symptoms for the hyperactive-impulsive subtype could include squirming and fidgeting in their seats or roaming around the room. They may wiggle their feet or talk incessantly. Children with hyperactivity may always seem to be on the go, sometimes dashing around touching whatever is in sight. Sitting still during a normal activity such as a story or movie can be a very difficult task. Impulsive children will oft times blurt out comments or display inappropriate emotions without regard to the consequences for their actions. It may be hard for them to wait for things or take turns in games and activities.

Since all children show some of the behaviors associated with ADHD, at one time or another, a diagnosis requires that the behavior is at such an elevated degree that it is inappropriate for the child’s age. The symptoms must also be persistent and present in a number of settings; at home, in school or during extracurricular activities. It is important to have a professional diagnosis of a child suspected of having ADHD

If your child has been observed, evaluated, and found to be suffering from ADHD, the next step is treatment. There are a wide range of treatment choices, ranging from counseling to medications. One medication that works for one child may not be affective for another.

source: healthnews.com