Generalized epilepsy with febrile seizures plus (GEFS+) spectrum: clinical manifestations and SCN1A mutations in Indonesian patients.

Generalized epilepsy with febrile seizures plus (GEFS+) is a childhood genetic epilepsy syndrome. GEFS+ includes a wide spectrum of clinical manifestations, and SCN1A mutations have frequently been reported among the GEFS+-related gene abnormalities. In this study, to clarify the distributions of the clinical subtypes, we analyzed 34 families with GEFS+ in Indonesia using the hospital records of the patients and questionnaires for the family members. The number of patients with febrile seizures plus (FS+), FS+ and afebrile generalized/partial seizures, borderline severe myoclonic epilepsy in infancy (SMEB) and severe myoclonic epilepsy in infancy (SMEI) were 9, 11, 7, and 7, respectively. Most patients had a family history of febrile seizures. Next, we performed molecular analyses to clarify the contributions of SCN1A mutations to the development of the GEFS+ subtypes. Only 3 of 34 probands showed SCN1A mutations. These mutations were two missense mutations, p.V1612I and p.C1756G, in two patients with SMEI and SMEB, and one silent mutation, p.G1762G, in a patient with FS+ and afebrile partial seizures. In conclusion, the majority of GEFS+ patients in Indonesia were not associated with SCN1A mutations. To detect the GEFS+-causing mutations, we must search and analyze other genes in these patients.