The purpose of this study is to characterize and assess the evolution of hearing impairment of patients with adulthood-onset bilateral sensorineural hearing loss carrying mutations on GJB2 gene.

This study aims to characterize patients with adulthood-onset bilateral sensorineural hearing loss not due to any underlying medical condition (likely due to a genetic cause) and to assess the evolution of hearing impairment of those carrying mutations in GJB2 gene.

Patients who present with adulthood-onset bilateral sensorineural hearing loss will be screened for the presence of mutation involved in hearing impairment. Patients with GJB2 mutations will be proposed to continue in a follow-up period.

Inclusion Criteria:

1. Female or Male patients ≥30 and ≤55 years old
2. Bilateral hearing loss first noticed after the age of 16 years old
3. Documented genotyping results showing mutations in GJB2 gene.

Exclusion Criteria:

1. Deafness with a known, non-genetic cause
2. To the opinion of the investigator, unable and/or unwilling to comply with all the protocol requirements and/or study procedures

Male and female participants aged ≥30 and ≤55 years old with bilateral hearing loss first noticed after the age of 16 years old.