Late onset autosomal dominant CMT2 neuropathy in a Costa Rican family

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Neurol Res. 2008 Sep 29.

Late onset autosomal dominant Charcot-Marie-Tooth 2 neuropathy in a

Costa Rican family.

Berghoff C, Berghoff M, Leal A, Morera B, Contreras C, Barrantes R,

Rautenstrauss B, Valle GD, Heuss D.

OBJECTIVE: To describe the clinical, electrophysiologic and

morphologic features of a Costa Rican family with an autosomal

dominant inherited Charcot-Marie-Tooth (CMT) neuropathy.

METHODS: The field study took place in Costa Rica, Central America.

Seven patients underwent neurological examinations and standard

electrodiagnostic tests, and a sural nerve biopsy was taken from one

patient. Fifteen family members were screened for gene defects

associated with CMT disease.

RESULTS: Characteristic features of this family were a late age of

onset (35-56 years), positive sensory symptoms and muscle cramps.

Based on electrodiagnostic and morphologic data, the patients were

classified as having a CMT2 neuropathy. The CMT1A duplication/HNPP

deletion and point mutations in genes PMP22, MPZ, Cx32 and EGR2

implicated in the most common types of CMT disease were excluded.

Subsequently, almost all known CMT loci were excluded by linkage

analysis.

DISCUSSION: Features of this family were a late age of onset and

positive sensory symptoms. This new autosomal dominant CMT neuropathy

is associated with an unknown gene defect.