- Bilateral tonic-clonic seizure (HP:0002069, a Human Phenotype Ontology term): A bilateral tonic-clonic seizure is a seizure defined by a tonic (bilateral increased tone, lasting seconds to minutes) and then a clonic (bilateral sustained rhythmic jerking) phase. Evidence: IEA. (OMIM:604403)
- Focal hemiclonic seizure (HP:0006813, a Human Phenotype Ontology term): A type of focal clonic seizure characterized by sustained rhythmic jerking rapidly involves one side of the body at seizure onset. Evidence: TAS. (OMIM:604403)
- Generalized myoclonic seizure (HP:0002123, a Human Phenotype Ontology term): A generalized myoclonic seizure is a type of generalized motor seizure characterized by bilateral, sudden, brief (<100 ms) involuntary single or multiple contraction of muscles or muscle groups of variable topography (axial, proximal limb, distal). Myoclonus is less regularly repetitive and less sustained than is clonus. Evidence: TAS. (OMIM:604403)
- Febrile seizure (within the age range of 3 months to 6 years) (HP:0002373, a Human Phenotype Ontology term): A febrile seizure is any type of seizure (most often a generalized tonic-clonic seizure) occurring with fever (at least 38 degrees Celsius) but in the absence of central nervous system infection, severe metabolic disturbance or other alternative precipitant in children between the ages of 3 months and 6 years. Evidence: IEA. (OMIM:604403)
- Childhood onset (HP:0011463, a Human Phenotype Ontology term): Onset of disease at the age of between 1 and 5 years. Evidence: IEA. (OMIM:604403)
- Atonic seizure (HP:0010819, a Human Phenotype Ontology term): Atonic seizure is a type of motor seizure characterized by a sudden loss or diminution of muscle tone without apparent preceding myoclonic or tonic event lasting about 1 to 2 seconds, involving head, trunk, jaw, or limb musculature. Evidence: IEA. (OMIM:604403)
- Generalized non-motor (absence) seizure (HP:0002121, a Human Phenotype Ontology term): A generalized non-motor (absence) seizure is a type of a type of dialeptic seizure that is of electrographically generalized onset. It is a generalized seizure characterized by an interruption of activities, a blank stare, and usually the person will be unresponsive when spoken to. Any ictal motor phenomena are minor in comparison to these non-motor features. Evidence: TAS. (OMIM:604403)
- Generalized tonic seizure (HP:0010818, a Human Phenotype Ontology term): A generalized tonic seizure is a type of generalized motor seizure characterized by bilateral limb stiffening or elevation, often with neck stiffening without a subsequent clonic phase. The tonic activity can be a sustained abnormal posture, either in extension or flexion, sometimes accompanied by tremor of the extremities. Evidence: IEA. (OMIM:604403)
- Variable expressivity (HP:0003828, a Human Phenotype Ontology term): A variable severity of phenotypic features. Evidence: TAS. (OMIM:604403)
- Focal-onset seizure (HP:0007359, a Human Phenotype Ontology term): A focal-onset seizure is a type of seizure originating within networks limited to one hemisphere. They may be discretely localized or more widely distributed, and may originate in subcortical structures. Evidence: TAS. (OMIM:604403)
- Autosomal dominant inheritance (HP:0000006, a Human Phenotype Ontology term): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. Evidence: IEA. (OMIM:604403)
These phenotypes are associated with the disease generalized epilepsy with febrile seizures plus, type 2 (OMIM:604403, an entry in Online Mendelian Inheritance in Man).