Atypical phenotype of charcot-marie-tooth disease type 1A.
Two sisters with a Charcot-Marie-Tooth disease type 1A (CMT1A) duplication, who had an unusual CMT1A clinical phenotype, are described. The 63-year-old proband presented with dysesthesia on the inner side of the right leg. Neurological examination revealed a localized sensory disturbance in the lower extremities and mild weakness in the feet and left hand. Her 61-year-old sister had experienced several episodes of acute paralysis, and neurological examination showed moderate, sensory-dominant polyneuropathy. A reduction of myelinated fibers with many onion-bulb formations were observed in the sural nerve of the proband, and electrophysiological studies showed reduced motor nerve conduction velocities in both sisters. To diagnose CMT1A, we developed a CMT1A duplication test based on detection of CMT1A-specific junction fragments using the long polymerase chain reaction (PCR) method. A 3.3-kb CMT1A-specific junction fragment was detected in both patients, and their neuropathy may therefore have been associated with CMT1A duplication.
Murakami
T
T
Department of Neurology, Kumamoto University School of Medicine, Honjo 1-1-1, Kumamoto 860-0811, Japan. tmurakami@mail.kuh.kumamoto-u.ac.jp
Oomori
H
H
Hara
A
A
Uyama
E
E
Mita
S
S
Uchino
M
M
D002607:Charcot-Marie-Tooth Disease / Q000175:diagnosis* / Q000235:genetics*; D017931:DNA Primers; D005192:Family Health; D005260:Female; D020440:Gene Duplication; D005820:Genetic Testing; D006801:Humans; D008875:Middle Aged; D009679:Nuclear Family; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic
D017931:DNA Primers