Evaluation of a Cohort of Congenital Deep Deafness Patients and/or With Auditory Neuropathy, Looking for DFNB9

ANAD is not a rare type of hearing loss. Nevertheless, its profile is heterogeneous and the pathology remain underdiagnosed. The investigators will screen all new patients with bilateral severe to profound HL, looking for DFNB9. They will analyse their electrophysiology (auditory potential, and otoacoustic emission), and their audio-vestibular profile, at an early stage and one year after inclusion. All patients will be seen in the genetic clinic. Also, the investigators will analyse all patients with ANAD profile and patients known with ANAD.

All informations will provide precise data base to allow a better understanding of the pathology. It might also lead to select the best candidates for future gene therapy

G1a / Inclusion Criteria:

• Child from 0 to 3 years old
• Child with severe to profound bilateral deafness newly diagnosed with:
• Average hearing threshold> 70 decibel on each ear
• and / or no response to 70 decibel PEA on each ear
• and / or no response to ASSR

G1b / Inclusion Criteria:

• Child under 16
• Child with newly diagnosed hearing neuropathy : tonal/vocal dissociation (when this is possible), and/or modified PEA, and/or discordant ASSR, and/or OEA present.

G2 / Inclusion Criteria:

• Adult patient under 25 or child
• Patient with deafness with auditory neuropathy
• Patient known to have 1 or 2 mutations of the otoferlin protein

Exclusion criteria

• Other type of deafness such as : unilateral deafness, deafness of transmission, malformation syndrome, known genetic familial deafness not DFNB9
• Patient without medical insurance
• Lack of consent to DNA sampling, of one or both biological parents (consent of the care)