GJB1 and Charcot-Marie-Tooth disease: The genetic causes of more than 90% of CMT cases are due to mutations in four genes including PMP22, GJB1, MFN2, and MPZ (Auer‐Grumbach et al., 2003; Chung, 2006; Nave et al., 2007; Timmerman et al., 2014), with PMP22 mutations alone accounting for ~70% of CMT1 cases while in CMT2, mutations in GJB1 and MFN2 are more frequent (Azzedine et al., 2012).