Charcot-Marie-Tooth disease type 1A

General Information (adopted from Orphanet):

Synonyms, Signs: CHARCOT-MARIE-TOOTH DISEASE, AUTOSOMAL DOMINANT, WITH FOCALLY FOLDED MYELIN SHEATHS, TYPE 1A
HEREDITARY MOTOR AND SENSORY NEUROPATHY IA
HMSN IA
CHARCOT-MARIE-TOOTH NEUROPATHY, TYPE 1A
HMSN1A
CMT1A
Microduplication 17p12
Number of Symptoms 37
OrphanetNr: 101081
OMIM Id: 118220
ICD-10: G60.0
UMLs: C0270911
MeSH:
MedDRA:
Snomed: 40632002

Prevalence, inheritance and age of onset:

Prevalence: No data available.
Inheritance: Autosomal dominant
[Orphanet]
Age of onset: Childhood
[Orphanet]

Disease classification (adopted from Orphanet):

Parent Diseases: Charcot-Marie-Tooth disease type 1
 -Rare genetic disease
 -Rare neurologic disease
Partial duplication of the short arm of chromosome 17
 -Rare developmental defect during embryogenesis
 -Rare genetic disease

Symptom Information: Sort by abundance 

1
(HPO:0000365) Hearing impairment 539 / 7739
2
(HPO:0003481) Segmental peripheral demyelination/remyelination 12 / 7739
3
(HPO:0003376) Steppage gait 41 / 7739
4
(HPO:0003383) Onion bulb formation 30 / 7739
5
(HPO:0004336) Myelin outfoldings 4 / 7739
6
(HPO:0001265) Hyporeflexia 208 / 7739
7
(HPO:0003431) Decreased motor nerve conduction velocity 51 / 7739
8
(HPO:0003382) Hypertrophic nerve changes 6 / 7739
9
(HPO:0001284) Areflexia 198 / 7739
10
(HPO:0002936) Distal sensory impairment 96 / 7739
11
(HPO:0003380) Decreased number of peripheral myelinated nerve fibers 30 / 7739
12
(HPO:0001288) Gait disturbance 318 / 7739
13
(HPO:0001838) Rocker bottom foot 85 / 7739
14
(HPO:0001822) Hallux valgus 70 / 7739
15
(HPO:0002751) Kyphoscoliosis 131 / 7739
16
(HPO:0001761) Pes cavus 225 / 7739
17
(HPO:0009027) Foot dorsiflexor weakness 45 / 7739
18
(HPO:0001178) Ulnar claw 8 / 7739
19
(HPO:0001760) Abnormality of the foot 96 / 7739
20
(HPO:0001765) Hammertoe 63 / 7739
21
(HPO:0001763) Pes planus 176 / 7739
22
(HPO:0001171) Split hand 72 / 7739
23
(HPO:0003693) Distal amyotrophy 118 / 7739
24
(HPO:0002460) Distal muscle weakness 122 / 7739
25
(HPO:0003449) Cold-induced muscle cramps 2 / 7739
26
(HPO:0003587) Insidious onset 11 / 7739
27
(OMIM) Distal limb muscle atrophy due to peripheral neuropathy 48 / 7739
28
(OMIM) 'Onion bulb' formation on nerve biopsy 6 / 7739
29
(OMIM) Myelin outfoldings may occur in a subset of patients 2 / 7739
30
(HPO:0000006) Autosomal dominant inheritance 2518 / 7739
31
(OMIM) Kyphoscoliosis may occur 4 / 7739
32
(OMIM) Segmental demyelination/remyelination on nerve biopsy 9 / 7739
33
(OMIM) Decreased number of myelinated fibers 6 / 7739
34
(HPO:0001425) Heterogeneous 132 / 7739
35
(HPO:0003677) Slow progression 134 / 7739
36
(HPO:0003621) Juvenile onset 105 / 7739
37
(HPO:0003828) Variable expressivity 130 / 7739

Associated genes:

ClinVar (via SNiPA)

Gene symbol Variation Clinical significance Reference

Additional Information:

Description: (OMIM) For a general phenotypic description and a discussion of genetic heterogeneity of Charcot-Marie-Tooth disease type 1, see CMT1B (118200).

CMT1A is the most common form of CMT. The average age of onset of clinical symptoms is ...

Diagnosis OMIM Matise et al. (1994) referred to the tandem duplication underlying CMT1A as resulting in segmental trisomy. The search for the CMT1A disease gene was misdirected and impeded because some chromosome 17 genetic markers that are linked to CMT1A ...
Clinical Description OMIM Bird et al. (1983) and Dyck et al. (1983) reported families of typical CMT1 except that linkage to the Duffy blood group locus (Fy) on chromosome 1, where CMT1B maps, was excluded. Whereas Dyck et al. (1983) could ...
Genotype-Phenotype Correlations OMIM Suter and Patel (1994) reviewed and discussed the curious finding that gene dosage and point mutations affecting the same gene can lead to a similar phenotype. They pointed to a possibly identical situation with Pelizaeus-Merzbacher disease (312080) in ...
Molecular genetics OMIM - Common 1.5-Mb Duplication on Chromosome 17p12-p11

See 601097.0001 for discussion of the work of Lupski et al. (1991) and others indicating that a DNA duplication on chromosome 17 in the p12-p11.2 region is frequently the ...

Population genetics OMIM Lupski et al. (1992) stated that CMT in all of its forms is the most common inherited peripheral neuropathy in humans, with a total prevalence rate of 1 in 2,500. In a series of 172 index cases of ...