Phenotypes associated with the disease epilepsy, familial adult myoclonic, 4 (OMIM:615127):
- Bilateral tonic-clonic seizure (HP:0002069): 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: PCS. (PMID:22713812)
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 3/13. (PMID:22713812)
- Seizure (HP:0001250): A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. Evidence: PCS. Frequency: 7/13. (PMID:22713812)
- Nonprogressive (HP:0003680): Applies to a disease manifestation that does not increase in scope or severity over the course of time, i.e., that does not worsen with age. Evidence: PCS. (PMID:22713812)
- Enhancement of the C-reflex (HP:0001340): Increase in amplitude of a long-loop response upon somatosensory evoked potential testing, representing an electrically evoked myoclonic response. Evidence: PCS. Frequency: 11/11. (PMID:22713812)
- Jerk-locked premyoclonus spikes (HP:0001351): Jerk-locked averaging (JLA) is used to record the timing and distribution of brain activity preceding brisk involuntary movements such as those observed in patients with myoclonus. JLA is capable of revealing a premyoclonus spike in the absence of paroxysmal activity in the routine EEG. Evidence: PCS. Frequency: 2/2. (PMID:22713812)
- Young adult onset (HP:0011462): Onset of disease at the age of between 16 and 40 years. Evidence: PCS. Frequency: 10/13. (PMID:22713812)
- EEG with polyspike wave complexes (HP:0002392): The presence of complexes of repetitive spikes and waves in EEG. Evidence: PCS. Frequency: 7/10. (PMID:22713812)
- Autosomal dominant inheritance (HP:0000006): 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: PCS. (PMID:31539032)
- Tremor (HP:0001337): An unintentional, oscillating to-and-fro muscle movement about a joint axis. Evidence: PCS. Frequency: 13/13. (PMID:22713812)
- Intellectual disability (HP:0001249): The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence. Evidence: PCS. Frequency: 0/13. (PMID:22713812)
- Myoclonus (HP:0001336): Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements. Evidence: PCS. Frequency: 13/13. (PMID:22713812)