Insights Into Genetic Causes of Childhood Epilepsies
Insights Into Genetic Causes of Childhood Epilepsies
A new study linked 2 novel genes to severe forms of childhood epilepsies. The results provide opportunities for exploring the origins and treatment of the disorders.
Identifying genes that may affect childhood epilepsy has been difficult. Many disease-linked genes have been found by tracking down mutations that are inherited along with the disease. However, the genetic mutations associated with childhood epilepsies tend to be new mutations that aren’t inherited—called spontaneous, or de novo, mutations.
The new study is a combined effort of 2 major projects to find the genetic causes of epilepsy, called Epilepsy 4000 and the Epilepsy Phenome/Genome Project. Largely funded by NIH’s National Institute of Neurological Disorders and Stroke (NINDS), researchers have collected DNA and clinical data from thousands of epilepsy patients and their relatives.
In this study, the researchers searched for mutations that are likely to cause 2 classical forms of epilepsy: infantile spasms and Lennox-Gastaut syndrome. The scientists compared the exomes (the protein-coding sections of the genome) of 264 epileptic children with those of their healthy parents to identify non-inherited, de novo mutations. The results appeared online in Nature on August 11, 2013.
The researchers observed mutations in several candidate genes. Advanced analysis techniques helped them identify 6 genes associated with the epilepsies. Four of these genes had already been linked to epilepsy, but 2 hadn’t (ALG13 and GABRB3). When the researchers looked at these 6 genes in healthy families, they found no significant excess of de novo mutations.
A deeper and broader analysis of the mutations helped the researchers estimate that up to 90 genes could carry epilepsy-causing mutations. They were also able to identify specific molecular pathways that may be involved in the disorder. This knowledge could lead to candidate drug targets for new treatments.
“We anticipate that further studies will identify many new disease-causing genes, and we intend to develop a watch list of the genes which summarizes their clinical characteristics in a way that will be helpful for doctors, patients and researchers,” says Dr. David Goldstein of Duke University Medical Center, a leader of the study.
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* The above story is reprinted from materials provided by National Institutes of Health (NIH)
** The National Institutes of Health (NIH) , a part of the U.S. Department of Health and Human Services, is the nation’s medical research agency—making important discoveries that improve health and save lives. The National Institutes of Health is made up of 27 different components called Institutes and Centers. Each has its own specific research agenda. All but three of these components receive their funding directly from Congress, and administrate their own budgets.