GJB2 and sensorineural hearing loss disorder: Nearly half of all inherited sensorineural hearing loss is attributed to mutations in one of four members of the 21 connexin gene family (Chan and Chang, 2014), although GJB2 gene (encoding Cx26) mutations linked to hereditary deafness are by far the most common (Duman and Tekin, 2012; Mammano, 2019).