Vocal Cord Paresis and Probable X-Linked Charcot-Marie-Tooth Disease With Novel GJB1 Mutation

We describe a Chinese family with a probable X-linked dominant inherited disorder characterized by early adult onset of distal muscle weakness and amyotrophy of four limbs, followed by severe disability of feet. The life expectancy of some patients is decreased due to severe respiratory failure associated with bilateral vocal cord involvement. The electrophysiological data showed predominantly the evidence of demyelization. Genetic analysis revealed that all tested patients from the family carried a novel c.186C>G mutation in the GJB1 gene, resulting in substitution of Serine for Arginine in the first extracellular loop domain of Cx32 protein. To our knowledge, this is the first time to describe this GJB1 mutation, which is associated with the rather severe phenotype of the X-linked Charcot-Marie-Tooth disease. The present report also provides further evidence for heterogeneity among the X-linked Charcot-Marie-Tooth disease.