The study aims to:~better describe the prevalence of cases of DFNB1A and DFNB9, including the type of mutations, and to assess the clinical course of the disease in children up to 10 years of age who have a moderate to profound deafness.~better understand the audiological and genetic characteristics of the participants with congenital versus evolutive DFNB1A and DFNB9 deafness.
The purpose of this study is to follow the natural history of non-syndromic hearing loss caused by mutations in two genes (GJB2 or OTOF) in children up to 10 years of age.