Charcot-Marie-Tooth disease and related genetic neuropathies

Wayne State University, Detroit, Michigan 48201, USA.
CONTINUUM Lifelong Learning in Neurology 02/2012; 18(1):39-59. DOI: 10.1212/01.CON.0000411567.34085.da
Source: PubMed

ABSTRACT The inherited peripheral neuropathies are a complex group of disorders caused by mutations in more than 50 genes. Scientifically, these disorders provide extensive information on molecular pathways that cause demyelination, axonal loss, and abnormal interactions between Schwann cells and the axons they ensheathe. Clinically, however, these neuropathies are confusing because it is difficult to determine what gene to test for in a given patient, inheritance patterns may differ among patients, and genetic testing is expensive. This review provides a biological context and guidelines to help neurologists better understand the basis and focus of genetic testing for these disorders.
In the past 5 years, many of the genetic causes of inherited neuropathies have been discovered and the phenotypes of inherited neuropathies have been characterized. Clinical trials of genetic neuropathies are now underway.
It is hoped that this review will lead to a better understanding of these fascinating neuropathies for health care professionals and that this improved understanding will facilitate treatment advances for these presently untreatable diseases.

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    • "Interestingly, some of these patients exhibit intellectual deficits (Genari et al., 2011). The typical CMT phenotype includes onset of predominantly motor length-dependent sensory and motor polyneuropathies within the first two decades of life associated with variable sensory manifestations, decreased or absent tendon jerks, and skeletal abnormalities, such as pes cavus, hammer toes, and scoliosis (Thomas et al., 1997; Marques et al., 2005; Patzko and Shy, 2012) However, marked clinical heterogeneity exists, even for the same mutation, in the same family and for identical twins (Marques et al., 1999). Genetic and non-genetic factors must therefore be involved. "
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