Hereditary motor and sensory neuropathy with deafness, mental retardation, and absence of sensory large myelinated fibers: confirmation of a new entity.

We describe two brothers, 11 and 13 years old, respectively, with an early-onset hereditary motor and sensory neuropathy, deafness, and mental retardation. Electrophysiological studies showed marked reduction of motor and sensory conduction velocity and absence of sensory action potentials. Sural nerve biopsy, performed in both patients, showed absence of large myelinated fibers with normal density of small myelinated fibers without axonal degeneration. Signs of demyelination were found only in the younger patient. We suggest that motorsensory neuropathy associated with deafness and mental retardation with absence of large myelinated fibers on sural nerve biopsy represents a distinct clinicopathological entity, which is transmitted in families probably as an autosomal recessive trait.

[1]  P. Tonali,et al.  A novel mitochondrial DNA point mutation in the tRNA(Ile) gene is associated with progressive external ophtalmoplegia. , 1996, Biochemical and biophysical research communications.

[2]  A. Harding.  From the syndrome of Charcot, Marie and Tooth to disorders of peripheral myelin proteins. , 1995, Brain : a journal of neurology.

[3]  A. C. Chinault,et al.  A yeast artificial chromosome contig spanning the Charcot-Marie-Tooth disease type 1A duplication region. , 1992, Human molecular genetics.

[4]  F. Gabreëls,et al.  Autosomal recessive form of hereditary motor and sensory neuropathy type I , 1992, Neurology.

[5]  M. Tabaton,et al.  Hereditary motor and sensory neuropathy with deafness, mental retardation and absence of large myelinated fibers , 1992, Journal of the Neurological Sciences.

[6]  Aravinda Chakravarti,et al.  DNA duplication associated with Charcot-Marie-Tooth disease type 1A , 1991, Cell.

[7]  G Hermanson,et al.  High-resolution mapping of human chromosome 11 by in situ hybridization with cosmid clones. , 1990, Science.

[8]  G. Bresnick,et al.  Optic atrophy, hearing loss, and peripheral neuropathy. , 1989, American journal of medical genetics.

[9]  R. Walker,et al.  Autosomal recessive hereditary motor and sensory neuropathy with mental retardation, optic atrophy and pyramidal signs. , 1987, Journal of neurology, neurosurgery, and psychiatry.

[10]  L. Graziani,et al.  X-linked motor-sensory neuropathy type-II with deafness and mental retardation: a new disorder. , 1985, American journal of medical genetics.

[11]  P. Beighton,et al.  Autosomal recessive inheritance of Charcot‐Marie‐Tooth disease associated with sensorineural deafness , 1984, Clinical genetics.

[12]  A. Harding,et al.  Peroneal muscular atrophy with pyramidal features. , 1984, Journal of neurology, neurosurgery, and psychiatry.

[13]  P K Thomas,et al.  Autosomal recessive forms of hereditary motor and sensory neuropathy. , 1980, Journal of neurology, neurosurgery, and psychiatry.

[14]  R. Rosenberg,et al.  Familial opticoacoustic nerve degeneration and polyneuropathy , 1967, Neurology.