GJB1 and sensory peripheral neuropathy: Mutations in the GJB1 gene, which encodes Cx32, are the leading cause of the X-linked dominant form of Charcot–Marie–Tooth disease (CMT1X or CMTX1), the second most common form of hereditary motor and sensory neuropathy and a disease for which there is no cure (Kleopa and Scherer, 2006; Kleopa et al., 2012).