www.medicalindependent.ie
(http://www.medicalindependent.ie/53278/rcsi_contributes_to_important_milestone_in_understanding_epilepsy)
RCSI contributes to ‘important milestone’ in understanding epilepsy
09 Sep 2014
RCSI researchers have played a leading role in a study recently published in The Lancet Neurology identifying specific genetic factors around epilepsy.
Over 34,000 people were involved in this study, including more than 8,000 with epilepsy. Participants were of European, Asian and African ancestry.
Two genes stood out as having broad implications for epilepsy, according to the study. One, a sodium channel subunit that regulates neuronal excitability (SCN1A), had previously been associated with certain familial and severe childhood epilepsies; this finding suggests it has an even broader role.
A second gene for the protein protocadherin, which helps bind cells together, was also strongly associated with epilepsy. This discovery was unexpected and suggests that the factors that contribute to common epilepsies are more complex than originally thought, and may involve the basic structure of the brain.
Prof Norman Delanty, RCSI Department of Molecular and Cellular Therapeutics and Beaumont Hospital, said: “This is an important milestone in our efforts to understand the genetics of epilepsy. Most people with epilepsy do not have a strong family history of the condition, but we know genes still play an important role. This work provides insight to the particular genetic factors that contribute to epilepsy in this population.”
Since the first identification of a single gene mutation that caused a particular type of epilepsy that runs in a family (Autosomal Dominant Nocturnal Frontal Lobe Epilepsy), the search for the inherited cause of epilepsy focused on families in which many members had the disease. It became clear that there were a number of such genes causing familial epilepsies, but there were family members who carried one of these genes and who did not have the condition.
Previous studies revealed more to the development of epilepsy than the single gene mutation, and subsequent research showed that epilepsies of all kinds were more common in some families than in others. That observation led epilepsy researchers to conclude that the risk for epilepsy was related to multiple genetic factors. Determining those factors among the thousands of genes active in people would greatly improve understanding of the biology of epilepsy.
Due to the huge variability in each person’s genetic makeup, finding the genes that increase the risk required evaluating thousands of people from different countries and different ethnic backgrounds. The International League Against Epilepsy created the ILAE Consortium on Complex Epilepsies (http://www.ilae.org/) in order to bring researchers together to increase efforts in developing better treatments.
Epilepsy is a brain disease that causes a person to have repeated seizures. It has a higher mortality rate than cancer and affects at least 50 million people worldwide. This work was supported, in part, by Epilepsy Ireland and the HRB.