Featured Research

from universities, journals, and other organizations

New insight into the genetic causes of epilepsy

Date:
December 8, 2013
Source:
American Epilepsy Society (AES)
Summary:
Scientists screening the DNA of large cohorts for known and suspected epilepsy associated genes are finding that, while some genes are implicated in discrete phenotypes or forms of epilepsy, other genes are implicated in a wider range of phenotypes. Although ion channel genes are a common cause of epilepsy, the researchers also report a significant number of epilepsy patients with mutations in non-ion channel genes. The studies have important implications for treatment, prognosis and risk counseling.

Scientists screening the DNA of large cohorts for known and suspected epilepsy associated genes are finding that, while some genes are implicated in discrete phenotypes or forms of epilepsy, other genes are implicated in a wider range of phenotypes. Although ion channel genes are a common cause of epilepsy, the researchers also report a significant number of epilepsy patients with mutations in non-ion channel genes. The studies have important implications for treatment, prognosis and risk counseling.

Targeted resequencing of 101 genes

Epilepsy affects about three percent of the population and comprises a wide constellation of primary and syndromic neurological disorders. The epileptic encephalopathies (EE) are the most severe of the epilepsies, distinguished by multiple refractory seizures, cognitive deficit, and poor developmental outcome. De novo mutations in several genes are known causes of EE, but the genetic etiology of the vast majority of these encephalopathies is unknown.

An investigative team of researchers led by Dr. Heather Mefford, M.D., Ph.D., from the University of Washington, Seattle, and Dr. Ingrid Scheffer, MBBS, Ph.D, at the University of Melbourne, Australia, resequenced 101 known and candidate epilepsy genes in more than 600 patients with EE to identify the genetic causes underlying their conditions. The team demonstrates emerging trends in how mutations in some genes cause specific disorders, while mutations in others cause a wide range of neurodevelopmental phenotypes. Furthermore the investigators described six new EE genes, four of which are not involved in neurotransmission at the synapse, but rather may regulate expression of other genes. (Platform A.07 / Abstract 8750891 -- Targeted Resequencing of 101 Known and Suspected Candidate Epilepsy Genes in 600 Patients with Severe Epilepsies Identifies Recurrently Mutated Genes.)

"Our study identifies pathogenic mutations in ~12% of our EE cohort, and has identified important new genes for this condition" says lead author, Gemma Carvill, Ph.D., of the University of Washington. "Understanding how these new EE genes cause epilepsy provides new avenues of research and, in the future, development of targeted therapies."

Molecular diagnostic testing of 1,600 individuals with epilepsy

In another report, GeneDx, a diagnostic laboratory in Gaithersburg, MD, presented results of diagnostic testing for up to 53 genes associated with major forms of primary and syndromic epilepsy in 1,600 patients to determine the etiology of their epilepsy. Overall, they found a known or predicted pathogenic genetic abnormality in 261 cases (16%), while patients with infantile onset epilepsy had an even higher positive diagnostic rate of about 20%.

These results indicate that at least 20% of cases have a Mendelian genetic form of epilepsy. Although mutations in ion channel genes are a common cause of epilepsy, half of all pathogenic mutations were identified in non-ion channel genes including some very rare causes of epilepsy. In one-third of patients with a disease-causing mutation, molecular test results had immediate implications for patient treatment or management. (Platform A.08 / Abstract 1749369 -- New Insights into the Spectrum of Pathogenic Variation in Epilepsy Gained from 1600 Individuals.)

According to Courtney Downtain, M.S., C.G.C., who presented the report, "Utilizing a multi-gene panel for epilepsy allowed us to identify disease-causing mutations in genes causing rare genetic forms of epilepsy, which were not primarily considered by the referring physicians. In addition, we are starting to appreciate the expanding phenotypic spectrum of many epilepsy-related genes. Our data demonstrate that mutations in many genes can result in similar clinical presentation, illustrating the utility of multi-gene panel testing."


Story Source:

The above story is based on materials provided by American Epilepsy Society (AES). Note: Materials may be edited for content and length.


Cite This Page:

American Epilepsy Society (AES). "New insight into the genetic causes of epilepsy." ScienceDaily. ScienceDaily, 8 December 2013. <www.sciencedaily.com/releases/2013/12/131208090244.htm>.
American Epilepsy Society (AES). (2013, December 8). New insight into the genetic causes of epilepsy. ScienceDaily. Retrieved August 22, 2014 from www.sciencedaily.com/releases/2013/12/131208090244.htm
American Epilepsy Society (AES). "New insight into the genetic causes of epilepsy." ScienceDaily. www.sciencedaily.com/releases/2013/12/131208090244.htm (accessed August 22, 2014).

Share This




More Health & Medicine News

Friday, August 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Two US Ebola Patients Leave Hospital Free of the Disease

Two US Ebola Patients Leave Hospital Free of the Disease

AFP (Aug. 21, 2014) Two American missionaries who were sickened with Ebola while working in Liberia and were treated with an experimental drug are doing better and have left the hospital, doctors say on August 21, 2014. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
Cadavers, a Teen, and a Medical School Dream

Cadavers, a Teen, and a Medical School Dream

AP (Aug. 21, 2014) Contains graphic content. He's only 17. But Johntrell Bowles has wanted to be a doctor from a young age, despite the odds against him. He was recently the youngest participant in a cadaver program at the Indiana University NW medical school. (Aug. 21) Video provided by AP
Powered by NewsLook.com
American Ebola Patients Released: What Cured Them?

American Ebola Patients Released: What Cured Them?

Newsy (Aug. 21, 2014) It's unclear whether the American Ebola patients' recoveries can be attributed to an experimental drug or early detection and good medical care. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins