Genetic defect found to cause severe epilepsy and mental retardation

October 12, 2010

BEER-SHEVA, Israel, October 12, 2010 -- A research team at Ben-Gurion University of the Negev and Soroka University Medical Center in Beer-Sheva, Israel has detected a genetic mutation resulting in a progressive disease of severe mental retardation and epilepsy beginning at infancy. The research was just published in the American Journal of Human Genetics.

The team, led by BGU Prof. Ohad Birk of the National Institute for Biotechnology in the Negev determined that the defect is associated with the production of the 21st amino acid, selenocysteine (SEC), which leads to progressive brain atrophy.

According to Prof. Birk, "One out of every 40 Jews of both Moroccan and Iraqi ancestry may be carriers of this mutation. As the disease is both severe and common, testing for these mutations is expected to become a routine prenatal genetic screening test in these two populations, enabling prevention of future cases."

It is believed that further research will identify other mutations in the same gene as the cause of mental retardation with epilepsy in other communities. As the disease is progressive, elucidation of its molecular mechanisms might open new venues to treatment, preventing disease progression.

The human genetic code, as deciphered some 50 years ago, encodes 20 amino acids which are the building blocks of all proteins in the human body. However, in recent years it became apparent that a 21st amino acid exists: selenium, entering the body in food, is incorporated in the human tissues into what is known as selenocysteine.

This 21st amino acid is unique in that it is encoded by what is normally a stop codon - that is, a DNA sequence that normally instructs the protein building system to end the chain of amino acids, terminating the generated protein. In contrast with most genes, some 25 genes have a unique component that manipulates the stop codon so that instead of terminating the evolving protein chain, it inserts at that point an SEC building block.
-end-
The research was conducted by Orly Agamy, a Ph.D. student in Prof. Birk's group and is published this week in the American Journal of Human Genetics. Drs. Bruria Ben Zeev, Tally Sagie, Dorit Lev and Dieter Soll also participated in the study.

The research was funded by the Morris Kahn Family Fund, the Legacy Heritage Fund and the Israel Science Foundation.

For more information, please contact Dr. Ohad Birk, Tel: 972-52-8795930 or obirk@bgu.ac.il

About American Associates, Ben-Gurion University of the Negev

American Associates, Ben-Gurion University of the Negev plays a vital role in sustaining David Ben-Gurion's vision, creating a world-class institution of education and research in the Israeli desert, nurturing the Negev community and sharing the University's expertise locally and around the globe. With some 20,000 students on campuses in Beer-Sheva, Sede Boqer and Eilat in Israel's southern desert, BGU is a university with a conscience, where the highest academic standards are integrated with community involvement, committed to sustainable development of the Negev. For more information, please visit www.aabgu.org.

American Associates, Ben-Gurion University of the Negev

Related Epilepsy Articles from Brightsurf:

Focal epilepsy often overlooked
Having subtler symptoms, a form of epilepsy that affects only one part of the brain often goes undiagnosed long enough to cause unexpected seizures that contribute to car crashes, a new study finds.

Antibodies in the brain trigger epilepsy
Certain forms of epilepsy are accompanied by inflammation of important brain regions.

Breaching the brain's defense causes epilepsy
Epileptic seizures can happen to anyone. But how do they occur and what initiates such a rapid response?

Using connectomics to understand epilepsy
Abnormalities in structural brain networks and how brain regions communicate may underlie a variety of disorders, including epilepsy, which is one focus of a two-part Special Issue on the Brain Connectome in Brain Connectivity, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers.

Epilepsy: Triangular relationship in the brain
When an epileptic seizure occurs in the brain, the nerve cells lose their usual pattern and fire in a very fast rhythm.

How concussions may lead to epilepsy
Researchers have identified a cellular response to repeated concussions that may contribute to seizures in mice like those observed following traumatic brain injury in humans.

Understanding epilepsy in pediatric tumors
A KAIST research team led by Professor Jeong Ho Lee of the Graduate School of Medical Science and Engineering has recently identified a neuronal BRAF somatic mutation that causes intrinsic epileptogenicity in pediatric brain tumors.

Can medical marijuana help treat intractable epilepsy?
A new British Journal of Clinical Pharmacology review examines the potential of medicinal cannabis -- or medical marijuana -- for helping patients with intractable epilepsy, in which seizures fail to come under control with standard anticonvulsant treatment.

Fertility rates no different for women with epilepsy
'Myth-busting' study among women with no history of infertility finds that those with epilepsy are just as likely to become pregnant as those without.

Do women with epilepsy have similar likelihood of pregnancy?
Women with epilepsy without a history of infertility or related disorders who wanted to become pregnant were about as likely as their peers without epilepsy to become pregnant.

Read More: Epilepsy News and Epilepsy Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.