- 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: TAS. Frequency: Obligate (HP:0040280). (ORPHA:2590)
- Myoclonus (HP:0001336): Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2590)
- Abnormal lower motor neuron morphology (HP:0002366): Any structural anomaly of the lower motor neuron. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2590)
- Functional motor deficit (HP:0004302). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2590)
- Lower limb muscle weakness (HP:0007340): Weakness of the muscles of the legs. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2590)
- Abnormal circulating enzyme concentration or activity (HP:0012379): Concentration or activity of an enzyme is above or below the limits of normal in the blood circulation. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2590)
- Atypical behavior (HP:0000708): Atypical behavior is an abnormality in a person's actions that can be controlled or modulated by the will of the individual. While abnormal behaviors can be difficult to control, they are distinct from other abnormal actions that cannot be affected by the individual's will. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Tremor (HP:0001337): An unintentional, oscillating to-and-fro muscle movement about a joint axis. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Recurrent aspiration pneumonia (HP:0002100): Increased susceptibility to aspiration pneumonia, defined as pneumonia due to breathing in foreign material, as manifested by a medical history of repeated episodes of aspiration pneumonia. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Generalized myoclonic seizure (HP:0002123): 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. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Clumsiness (HP:0002312): Lack of physical coordination resulting in an abnormal tendency to drop items or bump into objects. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Frequent falls (HP:0002359). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Respiratory insufficiency due to muscle weakness (HP:0002747). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Atonic seizure (HP:0010819): 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Typical absence seizure (HP:0011147): A typical absence seizure is a type of generalized non-motor (absence) seizure characterized by its sudden onset, interruption of ongoing activities, a blank stare, possibly a brief upward deviation of the eyes. Usually the patient will be unresponsive when spoken to. Duration is a few seconds to half a minute with very rapid recovery. Although not always available, an EEG would usually show 3 Hz generalized epileptiform discharges during the event. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
- Sensorineural hearing impairment (HP:0000407): A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Mental deterioration (HP:0001268): Loss of previously present mental abilities, generally in adults. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- High-frequency sensorineural hearing impairment (HP:0001757): A form of sensorineural hearing impairment that affects primarily the higher frequencies. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Waddling gait (HP:0002515): Weakness of the hip girdle and upper thigh muscles, for instance in myopathies, leads to an instability of the pelvis on standing and walking. If the muscles extending the hip joint are affected, the posture in that joint becomes flexed and lumbar lordosis increases. The patients usually have difficulties standing up from a sitting position. Due to weakness in the gluteus medius muscle, the hip on the side of the swinging leg drops with each step (referred to as Trendelenburg sign). The gait appears waddling. The patients frequently attempt to counteract the dropping of the hip on the swinging side by bending the trunk towards the side which is in the stance phase (in the German language literature this is referred to as Duchenne sign). Similar gait patterns can be caused by orthopedic conditions when the origin and the insertion site of the gluteus medius muscle are closer to each other than normal, for instance due to a posttraumatic elevation of the trochanter or pseudarthrosis of the femoral neck. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Inability to walk (HP:0002540): Incapability to ambulate. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Scoliosis (HP:0002650): The presence of an abnormal lateral curvature of the spine. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Respiratory failure (HP:0002878): A severe form of respiratory insufficiency characterized by inadequate gas exchange such that the levels of oxygen or carbon dioxide cannot be maintained within normal limits. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Eyelid myoclonus (HP:0025097): Marked, involuntary jerking of the eyelids. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Bilateral tonic-clonic seizure with generalized onset (HP:0025190): A bilateral tonic-clonic seizure with generalized onset is a type of bilateral tonic-clonic seizure characterized by generalized onset; these seizures rapidly engage networks in both hemispheres at the start of the seizure. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Myoclonic status epilepticus (HP:0032667): A type of motor status epilepticus with repeating bilateral sudden brief (less than 100 ms) involuntary single or multiple contraction of muscles or muscle groups of variable topography. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- Limb myoclonus (HP:0045084). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2590)
- 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: TAS. Frequency: Very rare (HP:0040284). (ORPHA:2590)
- Dysphagia (HP:0002015): Difficulty in swallowing. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:2590)
- Gait disturbance (HP:0001288): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2590)
These phenotypes are associated with the disease Spinal muscular atrophy-progressive myoclonic epilepsy syndrome (ORPHA:2590).
The following phenotypes are NOT associated with this disease:
- Flexion contracture (HP:0001371): A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints. Evidence: TAS. (ORPHA:2590)
- Hepatosplenomegaly (HP:0001433): Simultaneous enlargement of the liver and spleen. Evidence: TAS. (ORPHA:2590)
- Hoarse voice (HP:0001609): Hoarseness refers to a change in the pitch or quality of the voice, with the voice sounding weak, very breathy, scratchy, or husky. Evidence: TAS. (ORPHA:2590)
- Skin nodule (HP:0200036): Morphologically similar to a papule, but greater than either 10mm in both width and depth, and most frequently centered in the dermis or subcutaneous fat. Evidence: TAS. (ORPHA:2590)