[A sporadic case of Charcot-Marie-Tooth disease type 1 A associated with a duplication in chromosome 17 p11.2-p12].
Charcot-Marie-Tooth disease type 1A (CMT1A) is an autosomal dominant demyelinating peripheral neuropathy. Most patients with CMT1A including sporadic cases have been found to have a 1.5 megabase tandem DNA duplication in chromosome 17 p11.2-p12 (CMT1A duplication). We reported a 7-year-old girl with sporadic CMT 1 associated with the CMT1A duplication. The diagnosis of CMT 1 was based on the symmetrical distal muscle weakness, per cavus deformity, reduced motor and sensory nerve conduction velocities, and segmental de- and remyelinatin on sural nerve biopsy. To detect the CMT 1A duplication, peripheral myelin protein 22 (PMP-22) cDNA and a polymorphic marker in this region, VAW409 R3, were employed as probes for Southern blot analysis. Sporadic cases of autosomal dominant-CMT type 1 can not be clinically differentiated from recessive-CMT1. Testing for the CMT1A duplication is an important first step even in the molecular diagnosis of sporadic CMT1.
Inoue
M
M
Department of Pediatrics, Yamada Red Cross Hospital, Mie.
Kojima
M
M
Aikoh
H
H
Sugai
K
K
Murakami
N
N
Nonaka
I
I
Hayasaka
K
K
Yamamoto
M
M
Sobue
G
G
D002607:Charcot-Marie-Tooth Disease / Q000175:diagnosis / Q000235:genetics*; D002648:Child; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D005260:Female; D020440:Gene Duplication; D005799:Genes, Dominant; D006801:Humans; D009185:Myelin Proteins / Q000235:genetics
D009185:Myelin Proteins; C073687:PMP22 protein, human