GJB2 and hearing loss disorder: Some studies have concluded that the cochlear implant in patients with GJB2 gene-related hearing loss allows them to acquire voice recognition equal to or better when compared to prelingual deaf children, with deafness of unclear origin, or even with congenital hearing loss, such as those caused by cytomegalovirus (Sinnathuray et al., 2004; Green et al., 2002).