Dejerine-sottas disease with a novel de novo dominant mutation, Ser 149 Arg, of the peripheral myelin protein 22.
The Ser149Arg mutation of peripheral myelin protein 22 (PMP22) was found in a 19-year-old woman with a sporadic case of Dejerine-Sottas disease. The patient showed delayed motor development. She walked for the first time with support at the age of 2 years. Scoliosis developed at age 4 years. Her walking ability was best at age 11. Thereafter, she showed progressive muscle weakness and sensory disturbances in the distal extremities. At the age of 18 years, the use of a wheelchair became necessary. Motor and sensory nerve conduction studies showed absent motor and sensory responses on electrical stimulation of the limb nerves. A sural nerve biopsy specimen showed marked decreases in the numbers of both large and small myelinated fibers, abundant onion-bulb formation, and hypomyelination. Electron microscopic observation revealed the presence of demyelinated axons and myelin sheaths disproportionately thin relative to axon diameter. That this was a de novo mutation was established by parentage testing and PMP22 gene analysis of the parents. The mutation seems to be novel and dominant.
Ohnishi
A
A
Department of Neurology, School of Medicine, University of Occupational and Environmental Health, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan. ohnishi@uoeh-u.med.ac.jp
Yamamoto
T
T
Izawa
K
K
Yamamori
S
S
Takahashi
K
K
Mega
H
H
Jinnai
K
K
D000328:Adult; D001706:Biopsy; D005260:Female; D015417:Hereditary Sensory and Motor Neuropathy / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008854:Microscopy, Electron; D009185:Myelin Proteins / Q000235:genetics*; D010525:Peripheral Nerves / Q000473:pathology* / Q000503:physiopathology* / Q000648:ultrastructure; D013497:Sural Nerve / Q000473:pathology / Q000503:physiopathology / Q000648:ultrastructure
D009185:Myelin Proteins; C073687:PMP22 protein, human