ADHD Is A Genetic Disorder: Children With ADHD More Likely To Have Missing Or Duplicated Segments Of DNA

Jan. 28, 2011

ADHD Is a Genetic Disorder: Children With ADHD More Likely to Have Missing or Duplicated Segments of DNA

By Brain Balance of Vernon Hills Today at 4:33 p.m.


* Share on Facebook

* Share on Twitter

* Print

* Email




Exciting news has come out for children with ADHD. There is now direct evidence that ADHD is a genetic disorder. This study also points out the close similarity between the genetic variants affected by ADHD and the Autism and Schizophrenia variants that have already been widely publicized. The publication Science Daily first published this.


Scientists at Cardiff University found that children with ADHD were more likely to have small segments of their DNA duplicated or missing than other children.


The study also found significant overlap between these segments, known as copy number variants (CNVs), and genetic variants implicated in autism and schizophrenia, proving strong evidence that ADHD is a neurodevelopmental disorder — in other words, that the brains of children with the disorder differ from those of other children.


The research, published in the journal The Lancet, was largely funded by the Wellcome Trust, with additional support from Action Medical Research, the Medical Research Council and the European Union.


"We hope that these findings will help overcome the stigma associated with ADHD," says Professor Anita Thapar. "Too often, people dismiss ADHD as being down to bad parenting or poor diet. As a clinician, it was clear to me that this was unlikely to be the case. Now we can say with confidence that ADHD is a genetic disease and that the brains of children with this condition develop differently to those of other children."


ADHD is one of the most common mental health disorders in childhood, affecting around one in 50 children in the UK. Children with ADHD are excessively restless, impulsive and distractible, and experience difficulties at home and in school. Although no cure exists for the condition, symptoms can be reduced by a combination of medication and behavioural therapy.


The condition is highly heritable — children with ADHD are statistically more likely to also have a parent with the condition and a child with an identical twin with ADHD has a three in four chance of also having the condition. Even so, until now there has been no direct evidence that the condition is genetic and there has been much controversy surrounding its causes, which some people have put down to poor parenting skills or a sugar-rich diet.


The team at Cardiff University analysed the genomes of 366 children, all of whom had been given a clinical diagnosis of ADHD, against over 1,000 control samples in search of variations in their genetic make-up that were more common in children with the condition.


"Children with ADHD have a significantly higher rate of missing or duplicated DNA segments compared to other children and we have seen a clear genetic link between these segments and other brain disorders," explains Dr Nigel Williams. "These findings give us tantalising clues to the changes that can lead to ADHD."


The researchers found that rare CNVs were almost twice as common in children with ADHD compared to the control sample — and even higher for children with learning difficulties. CNVs are particularly common in disorders of the brain.


There was also significant overlap between CNVs identified in children with ADHD and regions of the genome which are known to influence susceptibility to autism and schizophrenia. Whilst these disorders are currently thought to be entirely separate, there is some overlap between ADHD and autism in terms of symptoms and learning difficulties. This new research suggests there may be a shared biological basis to the two conditions.


The most significant overlap was found at a particular region on chromosome 16 which has been previously implicated in schizophrenia and other major psychiatric disorders and spans a number of genes including one known to play a role in the development of the brain .


"ADHD is not caused by a single genetic change, but is likely caused by a number of genetic changes, including CNVs, interacting with a child's environment," explains Dr Kate Langley. "Screening children for the CNVs that we have identified will not help diagnose their condition. We already have very rigorous clinical assessments to do just that."


Dr John Williams, Head of Neuroscience and Mental Health at the Wellcome Trust, which has supported Professor Thapar's work for ten years, says: "These findings are testament to the perseverance of Professor Thapar and colleagues to prove the often unfashionable theory that ADHD is a brain disorder with genetic links. Using leading-edge technology, they have begun to shed light on the causes of what is a complex and often distressing disorder for both the children and their families."


Brain Balance of Mequon

This site uses Facebook comments to make it easier for you to contribute. If you see a comment you would like to flag for spam or abuse, click the "x" in the upper right of it. By posting, you agree to our Terms of Use.

Suburban News Roundup

E-mail Newsletter

Your link to the biggest stories in the suburbs delivered Thursday mornings.

Enter your e-mail address above and click "Sign Up Now!" to begin receiving your e-mail newsletter
Get the Newsletter!

Login or Register to manage all your newsletter preferences.

Community Watch

» River Lane Inn in Brown Deer sold to Pastiche owner Updated:  11/25

» Whitefish Bay Holiday Stroll coming on Friday 11/25

» Bomb squad examines grenade found in Brown Deer house 11/25

» Inspired by Popp, Homestead seizes fifth state football title 11/25

» Sport Shorts: Nov. 26, 2015 11/25

» Shorewood robbery suspects face charges 11/25

» River Lane Inn will become Pastiche 11/25

» Woodland champion Shorewood girls basketball team looks for third title 11/25

» Homestead girls basketball team has high expectations 11/25

» Highlanders rejoice over state football title 11/25

» Shorewood School District raises $1 million for STEAM programs 11/24

» Crews battle house fire in Brown Deer; 2 cats killed Updated:  11/23

» Cats, guinea pig die in fire 11/23

» Mequon woman reported missing 11/23

» Homestead wins fifth state football title, 28-12, over Waukesha West 11/20

» Build-your-own pizza place coming to Shorewood next year 11/20

» Shorewood families want to host Syrian refugees 11/20

» Updated state championship game rankings of area prep football teams and players 11/19

» Homestead football team faces uphill title fight against West 11/18

» Wolf and Zortman fill in each other's gaps well 11/18

» Apartments, assisted living pitched in Mequon development 11/18

» Mequon-Thiensville's Demond Means says MPS role won't interfere with his day job 11/18

» Hayes helps Brown Deer/USM swimming team set two program records 11/18

» Oak Leaf Trail extension links Milwaukee to Ozaukee County Updated:  11/18

» Jorn finishes swimming career well, leads Shorewood to 11th at state 11/18

View All Posts Got a tip? Welcome rss




Local Business Directory