Proximal spinal muscular atrophy type 2

General Information (adopted from Orphanet):

Synonyms, Signs: MUSCULAR ATROPHY, SPINAL, INFANTILE CHRONIC FORM
MUSCULAR ATROPHY, SPINAL, INTERMEDIATE TYPE
SMA II
SMA-II
SMA2
Chronic spinal muscular atrophy
Intermediate spinal muscular atrophy
Chronic infantile spinal muscular atrophy
Number of Symptoms 11
OrphanetNr: 83418
OMIM Id: 253550
ICD-10: G12.1
UMLs:
MeSH:
MedDRA:
Snomed:

Prevalence, inheritance and age of onset:

Prevalence: 1.42 of 100 000 [Orphanet]
Inheritance: Autosomal recessive
[Orphanet]
Age of onset: Neonatal
Infancy
[Orphanet]

Disease classification (adopted from Orphanet):

Parent Diseases: Proximal spinal muscular atrophy
 -Rare genetic disease
 -Rare neurologic disease

Symptom Information: Sort by abundance 

1
(HPO:0001308) Tongue fasciculations 18 / 7739
2
(HPO:0002378) Hand tremor 9 / 7739
3
(HPO:0002398) Degeneration of anterior horn cells 14 / 7739
4
(HPO:0002205) Recurrent respiratory infections 254 / 7739
5
(HPO:0003202) Skeletal muscle atrophy 281 / 7739
6
(HPO:0003457) EMG abnormality 78 / 7739
7
(HPO:0001324) Muscle weakness 859 / 7739
8
(HPO:0007269) Spinal muscular atrophy 24 / 7739
9
(HPO:0000007) Autosomal recessive inheritance 2538 / 7739
10
(OMIM) EMG shows neurogenic abnormalities 8 / 7739
11
(OMIM) Muscle weakness, proximal, symmetric (lower limbs more affected than upper limbs) due to motor neuronopathy 5 / 7739

Associated genes:

ClinVar (via SNiPA)

Gene symbol Variation Clinical significance Reference

Additional Information:

Description: (OMIM) Spinal muscular atrophy refers to a group of autosomal recessive neuromuscular disorders characterized by degeneration of the anterior horn cells of the spinal cord, leading to symmetric muscle weakness and atrophy. SMA is the second most common lethal, ...
Clinical Description OMIM Fried and Emery (1971) suggested the existence of a distinct form of spinal muscular atrophy intermediate in severity between the infantile form SMA type I and juvenile form SMA III. The intermediate form, which they designated SMA II, ...
Molecular genetics OMIM Matthijs et al. (1996) used an SSCP assay for the molecular diagnosis of 58 patients with SMA, including 12 patients (7 Belgian and 5 Turkish) with SMA II. This assay discriminates between the SMN gene (600354) and the ...