Proximal spinal muscular atrophy type 3

General Information (adopted from Orphanet):

Synonyms, Signs: MUSCULAR ATROPHY, JUVENILE
SPINAL MUSCULAR ATROPHY, MILD CHILDHOOD AND ADOLESCENT FORM
KUGELBERG-WELANDER SYNDROME
SMA III
SMA-III
KWS
SMA3
Kugelberg-Welander disease
SMA type 3
Juvenile spinal muscular atrophy
Number of Symptoms 16
OrphanetNr: 83419
OMIM Id: 253400
ICD-10: G12.1
UMLs:
MeSH:
MedDRA:
Snomed:

Prevalence, inheritance and age of onset:

Prevalence: 0.26 of 100 000 [Orphanet]
Inheritance: Autosomal recessive
[Orphanet]
Age of onset: Childhood
[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:0002398) Degeneration of anterior horn cells 14 / 7739
3
(HPO:0007289) Limb fasciculations 2 / 7739
4
(HPO:0002522) Areflexia of lower limbs 16 / 7739
5
(HPO:0001265) Hyporeflexia 208 / 7739
6
(HPO:0002378) Hand tremor 9 / 7739
7
(HPO:0007269) Spinal muscular atrophy 24 / 7739
8
(HPO:0003394) Muscle cramps 106 / 7739
9
(HPO:0003457) EMG abnormality 78 / 7739
10
(HPO:0001324) Muscle weakness 859 / 7739
11
(OMIM) Muscle weakness and atrophy, proximal 5 / 7739
12
(OMIM) Chronic denervation seen on EMG 2 / 7739
13
(OMIM) Muscle weakness, proximal, symmetric (lower limbs more affected than upper limbs) due to motor neuronopathy 5 / 7739
14
(OMIM) Neuropathic process seen on muscle biopsy 1 / 7739
15
(HPO:0000007) Autosomal recessive inheritance 2538 / 7739
16
(HPO:0003676) Progressive disorder 148 / 7739

Associated genes:

ClinVar (via SNiPA)

Gene symbol Variation Clinical significance Reference

Additional Information:

Description: (OMIM) SMA is an autosomal recessive neuromuscular disorder characterized by progressive proximal muscle weakness and atrophy affecting the upper and lower limbs. By convention, SMA is classified into 4 types: I (SMA1; 253300), II (SMA2; 253550), III (SMA3), and ...
Clinical Description OMIM Kugelberg and Welander (1956) reported 5 children, among the 12 offspring of normal parents, with a juvenile form of spinal muscular atrophy; 2 of the 5 were monozygotic twins.

Levy and Wittig (1962) described proximal muscular ...

Molecular genetics OMIM Matthijs et al. (1996) used an SSCP assay for the molecular diagnosis of 58 patients with SMA, including 8 patients (6 Belgian and 2 Turkish) with SMA III. The SSCP assay discriminates between the SMN gene (600354) and ...
Population genetics OMIM In a carrier screening of autosomal recessive mutations involving 1,644 Schmiedeleut (S-leut) Hutterites in the United States, Chong et al. (2012) identified deletion of SMN1 exon 7 in heterozygous state in 179 individuals among 1,415 screened and in ...