Phenotypes associated with the disease adult-onset proximal spinal muscular atrophy, autosomal dominant (OMIM:182980):
- Hyporeflexia (HP:0001265): Reduction of neurologic reflexes such as the knee-jerk reaction. Evidence: PCS. Frequency: 8/8. (PMID:15372378)
- EMG: neuropathic changes (HP:0003445): The presence of characteristic findings of denervation on electromyography (fibrillations, positive sharp waves, and giant motor unit potentials). Evidence: IEA. (OMIM:182980)
- Middle age onset (HP:0003596): A type of adult onset with onset of symptoms at the age of 40 to 60 years. Evidence: PCS. Frequency: 7/8. (PMID:15372378)
- Distal amyotrophy (HP:0003693): Muscular atrophy affecting muscles in the distal portions of the extremities. Evidence: PCS. Frequency: 1/8. (PMID:15372378)
- Muscle spasm (HP:0003394): Sudden and involuntary contractions of one or more muscles. Evidence: PCS. Frequency: 7/8. (PMID:15372378)
- Distal muscle weakness (HP:0002460): Reduced strength of the musculature of the distal extremities. Evidence: PCS. Frequency: 1/8. (PMID:15372378)
- Fasciculations (HP:0002380): Fasciculations are observed as small, local, involuntary muscle contractions (twitching) visible under the skin. Fasciculations result from increased irritability of an axon (which in turn is often a manifestation of disease of a motor neuron). This leads to sporadic discharges of all the muscle fibers controlled by the axon in isolation from other motor units. Evidence: PCS. Frequency: 8/8. (PMID:15372378)
- Spinal muscular atrophy (HP:0007269): Muscular weakness and atrophy related to loss of the motor neurons of the spinal cord and brainstem. Evidence: PCS. (PMID:15372378)
- Late young adult onset (HP:0025710): Onset of disease at an age of greater than or equal to 25 to under 40 years. Evidence: PCS. Frequency: 1/8. (PMID:15372378)
- Loss of ambulation (HP:0002505): Inability to walk in a person who previous had the ability to walk. Evidence: PCS. Frequency: 1/8. Onset: Middle age onset (HP:0003596). (PMID:15372378)
- Proximal amyotrophy (HP:0007126): Amyotrophy (muscular atrophy) affecting the proximal musculature. Evidence: PCS. Frequency: 6/8. (PMID:15372378)
- Proximal muscle weakness (HP:0003701): A lack of strength of the proximal muscles. Evidence: PCS. Frequency: 7/8. (PMID:15372378)
- 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:15372378)
- Tremor (HP:0001337): An unintentional, oscillating to-and-fro muscle movement about a joint axis. Evidence: PCS. Frequency: 1/8. (PMID:15372378)