Autosomal‐recessive and X‐linked forms of hereditary motor and sensory neuropathy in childhood

Abstract

The hereditary motor and sensory neuropathies (HMSNs, Charcot-Marie-Tooth neuropathies) are the most common degenerative disorders of the peripheral nervous system. In recent years a dramatic expansion has occurred in our understanding of the molecular basis and cell biology of the recessively inherited demyelinating and axonal neuropathies, with delineation of a number of new neuropathies. Mutations in some genes cause a wide variety of clinical, neurophysiologic, and pathologic phenotypes, rendering diagnosis difficult. The X-linked forms of HMSN represent at least 10%-15% of all HMSNs and have an expanded disease spectrum including demyelinating, intermediate, and axonal neuropathies, transient central nervous system (CNS) dysfunction, mental retardation, and hearing loss. This review presents an overview of the recessive and X-linked forms of HMSN observed in childhood, with particular reference to disease phenotype and neurophysiologic and pathologic abnormalities suggestive of specific diagnoses. These findings can be used by the clinician to formulate a differential diagnosis and guide targeted genetic testing.

New Genetic Mutation in a Patient with Charcot-Marie-Tooth Disease

“…We describe a new mutation in the GJB1 gene, located in Xq13.1, which encodes for the gap junction beta 1 protein called connexin 32 [2,3], in a case of demyelinating Charcot-Marie-Tooth disease with an X-linked dominant inheritance pattern. The involvement of this gene is the second most common genetic alteration after duplication in chromosome 17p11.2-p12 of the PMP 22 gene [3,4].…”

“…The involvement of this gene is the second most common genetic alteration after duplication in chromosome 17p11.2-p12 of the PMP 22 gene [3,4].…”

Human Genetic Disorders Caused by Mutations in Genes Encoding Biosynthetic Enzymes for Sulfated Glycosaminoglycans

“…Hereditary motor and sensory neuropathies are heterogeneous neurodegenerative disorders characterized by a progressive loss of function in the peripheral sensory nerves (70). Symptoms commonly include weakness, falls, and sensory loss often associated with cavus or planus foot deformity (70).…”

Neuropathies périphériques héréditaires

“…Les maladies de CMT (ou syndrome CMT) sont des neuropathies fréquentes, puisqu'elles représentent environ 40 % des neuropathies chroniques d'origine génétique ; leur prévalence est estimée à 4,7 à 36 pour 100 000 [2] (tableau I).…”