Corporate Banner
Satellite Banner
Scientific Community
Become a Member | Sign in
Home>News>This Article

Genetic Mutation Could Increase Understanding of ADHD

Published: Wednesday, November 27, 2013
Last Updated: Wednesday, November 27, 2013
Bookmark and Share
Absence of normal gene that expresses a protein involved in nerve cell communication results in seizures and hyperactivity.

Scientists at Trinity College Dublin have discovered that a mutation in a single gene involved in the functioning of the brain’s nervous system can lead to hyperactivity symptoms that are characteristic of Attention-Deficit Hyperactivity Disorder (ADHD).

Getting the nervous system wired up properly is a big job. The brain contains billions of different types of nerve cells, which all have to be connected in a very precise fashion. This circuitry self-assembles as an embryo grows, based on a developmental programme involving the actions of thousands of different genes.

The scientists discovered that a mutation in a single mouse gene, ‘Elfn1’, can have a big effect. Their new findings give impetus to discover whether mutations in Elfn1 in humans can give rise to similar symptoms and whether they might play a part in some patients with epilepsy and ADHD. These two conditions occur together far more often than expected by chance.

In an article just published in the international journal, PLOS ONE, Associate Professor in Genetics at Trinity, Kevin Mitchell, and Research Technical Officer, Dr Jackie Dolan, investigated the importance of the function played by Elfn1 and the protein it produces when expressed. They did this by experimentally removing it from some mice and comparing the effects against those seen in mice with the normal gene.

Although overall brain anatomy and patterns of connectivity remained normal, there was clear evidence of disturbance in brain function in individuals without Elfn1. Seizures occurred in some, and these became more common over time and were easily triggered by human interaction. Secondly, hyperactivity was observed, and this showed an unusual response to the stimulant, amphetamine.

Amphetamine normally causes hyperactivity in animals that have Elfn1 present, as it does in most humans. Here, it reduced the hyperactivity of the mice without the gene. This is similar to the situation in patients with ADHD, where amphetamine and related drugs have a paradoxical, calming effect. “These findings clearly show that removal of the Elfn1 gene affects brain circuits with multiple consequences for behaviour,” said Dr Dolan.

The seizures likely relate to the function of Elfn1 in dampening the response of the nervous system to strong stimuli in key brain structures called the cortex and hippocampus. However, the development of ADHD-like hyperactivity focused on a different brain structure, known as the habenula. This structure is part of a system that integrates information from multiple regions of the brain and regulates the activity of nerve cells that produce mood-regulating chemicals such as dopamine and serotonin.

Professor Mitchell said: “We are at the beginning of this process of figuring out how this gene works and understanding the consequences when it is mutated. But, these animals provide a unique model to investigate how subtle changes in brain development can ultimately result in aberrant brain function”.

Elfn1 was first discovered by Dr Dolan, Professor Mitchell and colleagues in 2007. The protein it produces when expressed allows communication from one nerve cell to another. In a study published in Science last year, Emily Sylwestrak and Anirvan Ghosh, of the University of California, San Diego, showed that the Elfn1 protein determined what kind of connection was made onto those nerve cells.

The new research, which was funded by Science Foundation Ireland, is available below. 

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,800+ scientific posters on ePosters
  • More than 4,000+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Scientists Discover Genetic Basis for Memory Formation with Implications for Neurological Diseases
Two genes linked to simple memory formation also regulate appropriate nerve responses that are lacking in related disease sufferers.
Monday, December 23, 2013
International Research Project Identifies a New Genetic Mutation that Helps Explain the Development of Eczema
Scientists have identified a new genetic mutation linked to the development of a type of eczema known as atopic dermatitis (AD).
Monday, November 04, 2013
New Genetic Mutation Helps Explain Development of Eczema
Researchers found that a mutation in the gene Matt/Tmem79 led to the development of spontaneous dermatitis in mice.
Monday, November 04, 2013
Scientists Propose a Molecular Explanation for Degenerative Disease
An international collaboration has shed new light on the origins and molecular causes of age related degenerative conditions including Motor Neurone Disease (MND).
Monday, August 19, 2013
Scientific News
Revolutionary Technologies Developed to Improve Outcomes for Lung Cancer Patients
Breath test to detect lung cancer brings oxygen directly to the wound.
Dementia Linked to Deficient DNA Repair
Mutant forms of breast cancer factor 1 (BRCA1) are associated with breast and ovarian cancers but according to new findings, in the brain the normal BRCA1 gene product may also be linked to Alzheimer’s disease.
New Gene Map Reveals Cancer’s Achilles’ Heel
Team of researchers switches off almost 18,000 genes
New Discovery Sheds Light on Disease Risk
Gaps between genes interact to influence the risk of acquiring disease.
Mathematical Model Helps Show How Zebrafish Get Their Stripes
The iconic yellow and blue stripes of zebrafish form dynamically as young fish develop and grow. A mathematical model developed by Brown University researchers helps to show how pigment cells interact to form the pattern.
Epigenome Influenced by Habitat and Lifestyle
Study on Pygmy hunter-gatherer populations and Bantu farmers in Central Africa shows that habitat and lifestyle can impact the epigenome.
Shining Light on Microbial Growth and Death Inside our Guts
Precise measurement of microbial populations in gastrointestinal tracts could be key to identifying novel therapies.
New Tech Vastly Improves CRISPR/Cas9 Accuracy
A new CRISPR/Cas9 technology developed by scientists at UMass Medical School is precise enough to surgically edit DNA at nearly any genomic location, while avoiding potentially harmful off-target changes typically seen in standard CRISPR gene editing techniques.
New Class of RNA Tumor Suppressors Identified
Two short, “housekeeping” RNA molecules block cancer growth by binding to an important cancer-associated protein called KRAS. More than a quarter of all human cancers are missing these RNAs.
Biologists Induce Flatworms to Grow Heads and Brains of Other Species
Findings shed light on role of a new kind of epigenetic signaling in evolution, could yield clues for understanding birth defects and regeneration.
Skyscraper Banner

SELECTBIO Market Reports
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,800+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,000+ scientific videos