EPILEPTIC SEIZURES AND SYNDROMES IN TWINS: THE IMPORTANCE OF GENETIC FACTORS
Abstract number :
1.196
Submission category :
Year :
2003
Submission ID :
3640
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Marianne J. Kjeldsen, Linda A. Corey, Kaare Christensen, Mogens L. Friis Department of Neurology, Odense University Hospital, Odense, Denmark; Department of Human Genetics, Virginia Commonwealth University, Richmond, VA; The Danish Twin Registry, Institut
It is the aim of the present study to examine the contribution of genetic factors to risk for seizures and epilepsy overall, as well as, to risk for the major epilepsy syndromes using a twin study design.
The study population was recruited from the nation-wide, population-based Danish Twin Registry located at the University of Southern Denmark, Odense, Denmark. A total of 34,076 twins were screened for epilepsy. Cases were confirmed and classified by two neurologists according to the classification systems of the International League Against Epilepsy (ILAE). Probandwise concordance rates were used to assess the similarity of MZ and DZ twins for seizures, epilepsy overall and each of the major epilepsy categories. Biometrical analysis was used to estimate heritability for epilepsy.
A total of 214 twin pairs with epileptic seizures and 190 pairs with epilepsy were ascertained. Significantly higher concordance rates were found for monozygotic (MZ) compared to dizygotic (DZ) twins for both epileptic seizures (0.56 for MZ and 0.21 for DZ pairs, p[lt]0.001) and for epilepsy (0.49 for MZ and 0.16 for DZ pairs, p[lt]0.001). Concordance rates were higher for generalized epilepsy (0.65 for MZ and 0.12 for DZ) than for localization-related epilepsy (0.30 for MZ and 0.10 for DZ). In twin pairs where both members had seizures, 83% of MZ and 65% of DZ pairs had the same major epilepsy syndrome. Genetic factors were found to account for 2/3 of the liability to epileptic seizures and for more than one half of the liability for epilepsy.
Analysis of this neurologist-verified epilepsy twin data set has confirmed that genetic factors have a substantial impact on the etiology of epileptic seizures as well as on the occurrence of both generalized and partial epilepsies.
[Supported by: In part by the following grants: NIH NINDS grant (NS-31564); The Clinical Research Institute, University of Southern Denmark; The grant committee of Consultancy Counsel, Odense University Hospital; The Danish Epilepsy Society Research Foundation and The Hede Nielsen Foundation.]