Abstracts

Rationale: Febrile seizures are the most common type of seizures in young children. A distinct autosomal dominant disorder, characterized by febrile seizures beyond the age of 6 and presentation of different generalized or focal seizures is defined as Generalized Epilepsies with Febrile Seizures (GEFS+). Previously, sodium channel and GABR2 mutations were identified and 5 subtypes of GEFS+ syndromes were classified with genetic characteristics. Most studies included sporadic families. In this study, we documented a large consanguineous family with febrile seizures and focal or generalized seizures. Methods: We identified a large multigenerational family with multiple consanguineous marriage and febrile seizures and epilepsies in a village about 3000 population. We interviewed 170 people and build a pedigree with the information acquired from the family members. We obtained informed consent of participation for collection of clinical and EEG data and DNA samples. This study was approved by the ethic committee of Yeditepe University. We undertook two field trips to interview and examine all available affected and unaffected family members, as well as to collect blood samples and obtain EEGs. EEGs were obtained with digital electroencephalographs. We recorded the information about presence of febrile or afebrile seizures, age of onset, frequency of seizures, precipitating and risk factors, semiology of seizures, the presence and nature of aura. The EEGs were evaluated by three independent blinded clinical neurophysiologists. The clinical and EEG findings were used to classify the seizure types and epilepsy syndromes according to international epilepsy syndrome and semiological seizure classifications. Pedigree: Since there were 1052 persons with 1517 quite complicated connections, representing parenthood connections, usual pedigree representation was impossible for this case. Therefore, we used Pajek (Program for Analysis and Visualization of Large Networks), which is frequently used in Complex Network research, as a visualization tool. Mutational analysis of SCN1a, 1b, GABRA g2 were negative. Results: Originally, the 5 core inconsanguineous families were settled down in this town. There were other affected members associated with our original pedigree; however we excluded these because lack of information to describe the relationship. There were 462 women, 477 men in the pedigree. We collected DNA samples from 170 affected and unaffected members. EEGs were obtained from 135 members. Forty patients with either focal generalized or febrile seizures were documented. The most probable gene mutations could not find. Conclusions: Genetic studies are important in such consanguineous marriages to reveal novel genes. To identify novel genes and search for changes in genes already associated with the existing phenotypes.