X‐linked motor‐sensory neuropathy type‐II with deafness and mental retardation: A new disorder

Abstract

We report on a family with an apparently X-linked neuromuscular disease. Electrophysiologic tests and electron microscopic studies are consistent with the diagnosis of hereditary motor sensory neuropathy type II (HMSN-II), one form of Charcot-Marie-Tooth disease. The manner of inheritance, the observation that males are severely affected from infancy, and the frequent association of deafness and/or mental retardation with the neuromuscular disorder are not usual for HMSN-II and suggest that this family may have a previously undescribed genetic disorder. The peripheral neuropathy did not appear to be linked to the Xg blood group. Minor abnormalities of sensory nerve conduction, electromyography, and hearing were separately identified in female relatives in this family, but were not consistent enough to be useful in the identification of carriers for this gene.

Perrault syndrome: Evidence for progressive nervous system involvement

“…These represent a large, heterogeneous group of disorders. Motor and sensory neuropathy with X-linked deafness and MR was described by Cowchock et al [1985] and by Hamiel et al [1993]. An autosomal dominant form of HSMN with sensorineural deafness and early-onset dementia was reported by Wright and Dick [1995] in a large kindred and by Hamiel et al [1993] in another family.…”

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

“…A few patients mostly with autosomal recessive HMSN have a variable combination of additional clinical manifestations such as optic atrophy, sensorineural deafness, pyramidal signs, mental retardation, pigmentary retinopathy, agenesis of corpus callosum, and characteristic face [Rosenberg and Chutorian, 1967;Campeanu and Morariu, 1970;Andermann, 1981;Cornell et al, 1984;Harding and Thomas, 1984;Cowchock et al, 1985;Macdermot and Walker, 1987;Hagemoser et al, 1989;Mancardi et al, 1992]. This heterogeneous group of disorders, called ''HMSN with additional features'' or ''complex forms of HMSN'' by Harding and Thomas [1980] and Harding [1995], is nosologically illdefined and should be considered apart from HMSN with pure peripheral nervous system involvement.…”

X‐linked neuropathy of the Charcot–Marie–Tooth type

“…Cowchock et al described apparently X-linked recessive transmission of a form of axonal motor-sensory neuropathy associated with deafness and mental retardation [36].…”