[Hereditary neuropathies].

Hereditary neuropathies are the most frequent genetically determined disease in neurology. The peripheral motor and sensory form is the Charcot-Marie-Tooth disease. The underlying genetic defects are now known for many of the demyelinating form. Several studies have identified the mutations on genes coding proteins of peripheral myelin. This has important implications for both diagnosis and genetic counselling in this group of conditions. The genetic defect in most cases of familial amyloid polyneuropathy is better known and should be considered especially in late-onset forms.