Nabbout et al. (2002) reported 2 unrelated French families with a simple, pure form of febrile seizures. The trait was inherited in an autosomal dominant pattern in both families. Age at seizure onset ranged from 9 months to ... Nabbout et al. (2002) reported 2 unrelated French families with a simple, pure form of febrile seizures. The trait was inherited in an autosomal dominant pattern in both families. Age at seizure onset ranged from 9 months to 2.5 years; seizures ended by age 5 years in all patients. All cases had generalized seizures: tonic-clonic in most patients, but hypertonic and hypotonic seizures also occurred. Most seizures were brief, lasting from 1 to 5 minutes, but lasted up to 10 minutes in 3 patients. The mean number of seizures in both families was 3. All affected individuals had normal psychomotor development.