ORPHA:70
Proximal spinal muscular atrophy
Synonyms: SMA
- Type
- Disease
- Group
- Disorder
- Inheritance
- Autosomal recessive
- Age of onset
- All ages
- Status
- active
A group of rare genetic motor neuron disorders caused by degeneration of alpha motor neurons in the spinal cord and lower brainstem. It leads to progressive muscle weakness predominantly affecting proximal lower limb muscles. Severity varies from severe infantile-onset forms to milder, slowly progressive adult-onset types.
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Names in Orphadata languages
12 of 12 languages| Lang | Name | Synonyms |
|---|---|---|
| en | Proximal spinal muscular atrophy | SMA |
| fr | Amyotrophie spinale proximale | ASA · SMA |
| de | Spinale Muskelatrophie, proximale | = en |
| es | Atrofia muscular espinal proximal | AME · SMA |
| it | Atrofia muscolare spinale prossimale | = en |
| nl | Proximale spinale spieratrofie | Proximale spinale musculaire atrofie · SMA |
| pt | Atrofia muscular espinhal proximal | = en |
| pl | Rdzeniowy zanik mięśni | = en |
| cs | Proximální spinální svalová atrofie | SMA · Spinální muskulární atrofie |
| uk | Проксимальна спінальна мязова атрофія | = en |
| zh | 近端脊髓性肌萎缩 | = en |
| tr | Proksimal spinal kas atrofisi | = en |
Definition in:
2
Cross-references
qualifier = Orphanet mapping relation| Source | Code | Qualifier | ICD relation | Validation |
|---|---|---|---|---|
| OMIM | 253300 | BTNT | validated | |
| OMIM | 253400 | BTNT | validated | |
| OMIM | 253550 | BTNT | validated | |
| OMIM | 271150 | BTNT | validated | |
| ICD-10 | G12.0 | NTBT | attributed | validated |
| ICD-10 | G12.1 | NTBT | attributed | validated |
| ICD-11 | 8B61.Y | NTBT | index | validated |
| MONDO | 0019079 | E | validated | |
| UMLS | C4024957 | E | validated | |
| GARD | 4531 | E | validated |
E exact · NTBT this ORPHAcode is narrower than the target · BTNT broader than the target · ND not decided.
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Classification
Preferential parent (Orphanet linearisation):
Parents in the classifications (1):
- ORPHA:98505Genetic motor neuron disease
rare genetic diseases; rare neurological diseases
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Genes
0 direct · 11 via subtypesOrphanet records no gene directly on this code.
Recorded by Orphanet on subtypes of this disorder:
| Gene | Subtype | Association | Status | HGNC | Ensembl | OMIM | Locus | Name | Source of validation |
|---|---|---|---|---|---|---|---|---|---|
| SMN1 | ORPHA:83330Proximal spinal muscular atrophy type 1 | Disease-causing germline mutation(s) in | Assessed | HGNC:11117 | ENSG00000172062 | 600354 | 5q13.2 | survival of motor neuron 1, telomeric | 20301526[PMID] |
| SMN1 | ORPHA:83418Proximal spinal muscular atrophy type 2 | Disease-causing germline mutation(s) in | Assessed | HGNC:11117 | ENSG00000172062 | 600354 | 5q13.2 | survival of motor neuron 1, telomeric | 20301526[PMID] |
| SMN1 | ORPHA:83419Proximal spinal muscular atrophy type 3 | Disease-causing germline mutation(s) in | Assessed | HGNC:11117 | ENSG00000172062 | 600354 | 5q13.2 | survival of motor neuron 1, telomeric | 20301526[PMID] |
| SMN1 | ORPHA:83420Proximal spinal muscular atrophy type 4 | Disease-causing germline mutation(s) in | Assessed | HGNC:11117 | ENSG00000172062 | 600354 | 5q13.2 | survival of motor neuron 1, telomeric | 20301526[PMID] |
| NAIP | ORPHA:83330Proximal spinal muscular atrophy type 1 | Modifying germline mutation in | Assessed | HGNC:7634 | ENSG00000249437 | 600355 | 5q13.2 | NLR family apoptosis inhibitory protein | 11912351[PMID] |
| NAIP | ORPHA:83418Proximal spinal muscular atrophy type 2 | Modifying germline mutation in | Assessed | HGNC:7634 | ENSG00000249437 | 600355 | 5q13.2 | NLR family apoptosis inhibitory protein | 11912351[PMID] |
| NAIP | ORPHA:83419Proximal spinal muscular atrophy type 3 | Modifying germline mutation in | Assessed | HGNC:7634 | ENSG00000249437 | 600355 | 5q13.2 | NLR family apoptosis inhibitory protein | 11912351[PMID] |
| SMN2 | ORPHA:83330Proximal spinal muscular atrophy type 1 | Modifying germline mutation in | Assessed | HGNC:11118 | ENSG00000205571 | 601627 | 5q13.2 | survival of motor neuron 2, centromeric | 20301526[PMID] |
| SMN2 | ORPHA:83418Proximal spinal muscular atrophy type 2 | Modifying germline mutation in | Assessed | HGNC:11118 | ENSG00000205571 | 601627 | 5q13.2 | survival of motor neuron 2, centromeric | 20301526[PMID] |
| SMN2 | ORPHA:83419Proximal spinal muscular atrophy type 3 | Modifying germline mutation in | Assessed | HGNC:11118 | ENSG00000205571 | 601627 | 5q13.2 | survival of motor neuron 2, centromeric | 20301526[PMID] |
| SMN2 | ORPHA:83420Proximal spinal muscular atrophy type 4 | Modifying germline mutation in | Assessed | HGNC:11118 | ENSG00000205571 | 601627 | 5q13.2 | survival of motor neuron 2, centromeric | 20301526[PMID] |
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Prevalence and incidence
3 records| Type | Class | Value | Area | Qualification | Validation | Source |
|---|---|---|---|---|---|---|
| Annual incidence | 1-9 / 100 000 | 2.6 / 100 000 | Europe | Value and class | Validated | European Medicines Agency[OTHER] |
| Prevalence at birth | 1-5 / 10 000 | 20 / 100 000 | Europe | Value and class | Not yet validated | 23107878[PMID] |
| Point prevalence | 1-9 / 100 000 | — | Europe | Class only | Not yet validated | ORPHANET |
Value is Orphadata's ValMoy: the mean estimate per 100 000 for prevalence and incidence, the number of cases or families for case reports.
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HPO phenotypes
50 annotations · validated 2021-04-12| HPO | Term (as annotated by Orphanet) | Diagnostic |
|---|---|---|
| Very frequent (99-80%) | ||
| HP:0003701 | Proximal muscle weakness | |
| HP:0003202 | Skeletal muscle atrophy | |
| Frequent (79-30%) | ||
| HP:0001284 | Areflexia | |
| HP:0003327 | Axial muscle weakness | |
| HP:0001283 | Bulbar palsy | |
| HP:0003551 | Difficulty climbing stairs | |
| HP:0009046 | Difficulty running | |
| HP:0002460 | Distal muscle weakness | |
| HP:0002015 | Dysphagia | |
| HP:0012378 | Fatigue | |
| HP:0001288 | Gait disturbance | |
| HP:0002540 | Inability to walk | |
| HP:0004878 | Intercostal muscle weakness | |
| HP:0002643 | Neonatal respiratory distress | |
| HP:0002033 | Poor suck | |
| HP:0003731 | Quadriceps muscle weakness | |
| HP:0002100 | Recurrent aspiration pneumonia | |
| HP:0004891 | Recurrent infections due to aspiration | |
| HP:0001315 | Reduced tendon reflexes | |
| HP:0002747 | Respiratory insufficiency due to muscle weakness | |
| HP:0001308 | Tongue fasciculations | |
| HP:0031108 | Triceps weakness | |
| HP:0030319 | Weakness of facial musculature | |
| Occasional (29-5%) | ||
| HP:0006844 | Absent patellar reflexes | |
| HP:0001631 | Atrial septal defect | |
| HP:0002019 | Constipation | |
| HP:0001558 | Decreased fetal movement | |
| HP:0003698 | Difficulty standing | |
| HP:0009053 | Distal lower limb muscle weakness | |
| HP:0008959 | Distal upper limb muscle weakness | |
| HP:0001349 | Facial diplegia | |
| HP:0001371 | Flexion contracture | |
| HP:0002020 | Gastroesophageal reflux | |
| HP:0002578 | Gastroparesis | |
| HP:0001263 | Global developmental delay | |
| HP:0002827 | Hip dislocation | |
| HP:0001252 | Hypotonia | |
| HP:0002791 | Hypoventilation | |
| HP:0006380 | Knee flexion contracture | |
| HP:0001270 | Motor delay | |
| HP:0002828 | Multiple joint contractures | |
| HP:0001319 | Neonatal hypotonia | |
| HP:0002421 | Poor head control | |
| HP:0002878 | Respiratory failure | |
| HP:0002091 | Restrictive ventilatory defect | |
| HP:0002650 | Scoliosis | |
| HP:0002942 | Thoracic kyphosis | |
| Very rare (<4-1%) | ||
| HP:0001662 | Bradycardia | |
| HP:0002987 | Elbow flexion contracture | |
| HP:0001942 | Metabolic acidosis | |
Run the differential on the 2 obligate / very frequent terms
Annotation source: 20301526[PMID]_29478602[PMID]
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Sources for this card
- Orphanet page: orpha.net/en/disease/detail/70
- This record as JSON: /data/d/70.json