Epilepsy gene mutations found
An international study has discovered new genetic mutations that cause some of the most severe childhood epilepsies, opening the way to help find treatments.
The global study, led by the University of Melbourne and Austin Hospital, Duke University and the University of California, San Francisco, used advanced gene technology known as exome sequencing to identify new genes that cause severe childhood epilepsies.
Exomes essentially represent all of a person’s genes. Their DNA sequences provide the instructions for constructing all the proteins made by the body.
In one group of patients, the researchers discovered two new genes and 25 epilepsy-causing mutations, suggesting there will be common pathways to target epilepsies with drugs and other therapies.
The study, published in Nature, was part of a larger research project analysing 4000 genomes from epilepsy patients around the world.
Study co-leader, Professor Sam Berkovic Director of the Epilepsy Research Centre at the University of Melbourne and Austin Hospital, said it represented a major advance in how we analyse epilepsies, helping researchers to better identify their genetic causes and improve treatment options.
“These findings will help to fast track discoveries of the genetic causes of some of the most devastating childhood epilepsies, many of which had been previously unknown,” he said.
The study was part of a $25 million worldwide project, funded by the National Institutes of Health (NIH), called Epilepsy 4000 (Epi4K).
Epi4K’s mission is to use the latest genetic techniques to sequence and analyse DNA from 4000 epilepsy patients and their relatives.
The researchers in this study compared exome sequences of 264 children with the sequences of their parents who do not have epilepsy. Differences in the sequences were analysed using a number of statistical tools to identify potential disease causing mutations.
Dr David Goldstein, Director of the Human Genome Variation Center at Duke University Medical Center and a leader of the study, said the research opened up new paths for further exploration.
“This moderately-sized study identified an unusually large number of disease-causing mutations and provides a wealth of new information for the epilepsy research community to explore,” he said.
A co-chief investigator on the study, paediatric neurologist Professor Ingrid Scheffer of the University of Melbourne and the Florey Institute, Austin Hospital said “solving the cause of these children’s epilepsy is a huge step forward in understanding why they are sick and the beginning of the development of targeted therapies”.
The researchers estimated that up to 90 genes could carry epilepsy-causing mutations and that many of the mutations implicated in the risk of epilepsy had been previously associated with other diseases such as autism.
“These promising results highlight the strength of supporting large international research teams devoted to studying the genetics behind highly complex neurological disorders,” said Dr Story Landis, Director of the NIH’s National Institute of Neurological Disorders and Stroke.