Juvenile myoclonic epilepsy: the gene hunt
This research was completed on 14 April 2011
Published on 13 June 2012
Around five to eleven per cent of people with epilepsy have juvenile myoclonic epilepsy (JME), which typically starts in late childhood.1 Many rely on lifelong drug treatment to control their seizures, often at the expense of unpleasant side effects. As many as 15 per cent find existing drugs do not work for them.1 Dr Kate Everett of the Institute of Child Health,* London, has identified one probable genetic cause of JME, and is looking for more, with the ultimate aim of improving diagnosis and treatment.
* Dr K Everett now based at St George’s, University of London
What's the problem and who does it affect?
Most people with JME, a common form of epilepsy, are just 12 to 18 years old when they first develop symptoms.1 They experience three types of seizures, which can all be quite frightening: involuntary jerks, normally of the limbs; complete loss of consciousness with uncontrolled jerking movements; and brief losses of awareness.1
‘Fortunately, most children with JME find medication controls their seizures,’ says Dr Everett. ‘However, they often remain dependent on medication for the rest of their lives and all of the currently available drugs can cause unpleasant side effects. Some, for example, put the health of babies at risk if taken during pregnancy.’
Sadly, medication does not help everyone. ‘As many as 15 per cent of JME sufferers find existing medications do not work for them, meaning they continue to have seizures, which can be extremely disruptive,’ continues Dr Everett.1
Epilepsy can hinder a child’s education and their social development, particularly if seizures are uncontrolled. Children are sometimes excluded from everyday school activities, such as sports, because of the potential risks involved. The stigma that can still be attached to epilepsy can be particularly troublesome for children and teenagers, with many feeling awkward about being ‘different’ from their peers.
What did the project achieve?
Dr Everett’s on-going work aims to boost understanding of the genetic factors that cause JME, a condition that often runs in families.
‘We have been studying three large, extended families affected by JME,’ explains Dr Everett. ‘We have identified the likely genetic cause of JME in one family and we are now trying to find out whether this gene is responsible for JME in the wider population. As JME may result from a range of different genetic changes, we are looking for other changes that might be linked to the condition in the other two families.’
Knowing more about the genetic causes of JME could lead to better diagnosis and, eventually, to new treatments. “At the moment, it can take a long time for children to receive a diagnosis,” explains Dr Everett. “In the meantime, they continue to suffer seizures, which can impact profoundly upon their development, social interactions and quality of life. Once diagnosed, children often have to try several different drugs, in a rather ’hit-and-miss’ approach, until something works. Understanding the genetic basis of JME could speed up diagnosis and help when choosing the best treatment for each child. Eventually, it may also lead to new treatments.’
What are the researchers' credentials?
|Project Leader||Dr K Everett PhD|
|Location||Molecular Medicine Unit, UCL Institute of Child Health (Dr K Everett now based at St George’s, University of London)|
|Grant awarded||23 July 2009|
|Start date||1 November 2009|
|End date||14 April 2011|
|Acknowledgements||This project was supported by The Alison Hillman Charitable Trust and Next Plc|
We do not provide medical advice. If you would like more information about a condition or would like to talk to someone about your health, contact NHS Choices or speak to your GP. Please see our useful links page for some links to health information, organisations we are working with and other useful organisations. We hope you will find these useful. We are not responsible for the content of any of these sites.
The project leader, Dr Kate Everett, is geneticist who specialises in determining the genetic causes of childhood disorders such as epilepsy. Dr Everett is working with Dr Robert Robinson, a Consultant at Great Ormond Street Hospital, who specialises in complex epilepsy. He has extensive clinical experience and has published widely.
1. Renganathan R, Delanty N. Juvenile myoclonic epilepsy: under-appreciated and under-diagnosed. Postgrad Med J 2003; 79: 78-80.