[Hereditary motor-sensory neuropathies (Charcot-Marie-Tooth syndrome) and related neuropathies. Current classification and genotype-phenotype correlation].

Charcot-Marie-Tooth (CMT) disease is the most common inherited disorder of the peripheral nervous system with an incidence of 40:100,000. Clinically, it is characterized by distal muscle weakness and wasting, primarily of the legs and later of the arms, foot deformity, diminished or absent tendon reflexes, and mild-to-moderate sensory loss. Molecular genetic studies over the past 2 decades have revealed the genetic heterogeneity of this disorder and the identification of different genes or gene loci, respectively. Therefore, a current CMT classification though constantly changing due to ongoing detection of further genetic defects must take into consideration both phenotypic and genotypic criteria. Since certain clinical features appear to be associated with specific genetic subtypes, we provide a detailed description of characteristic phenotypic variants to facilitate differential diagnosis and allow more precise referral to subsequent genetic investigations.