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 16 years of age.
Aged ≤ 16 years on the date of signed informed consent for cohort 1 and ≤ 10 years for cohort 2;
With a diagnosis of non-syndromic, bilateral, mild to profound, sensorineural hearing loss (according to the American Speech Language-Hearing Association);
With documented genotyping results showing mutation(s) in GJB2 or OTOF genes;
Written informed consent as required by local regulations.
Other type of deafness, such as unilateral deafness, persistent conductive deafness, malformation syndrome, syndromic deafness, known familial deafness linked to mutations in other genes than OTOF or GJB2;
Documented genotyping results showing pathogenic mutation(s) in other gene(s) than GJB2 or OTOF genes in the tested panel;
Unable and/or unwilling to comply with all the protocol requirements and/or study procedures.
Male and female participants aged ≤ 16 years at selection, with a diagnosis of bilateral, moderate to profound, sensorineural, non-syndromic hearing loss, with genotyping results showing mutation(s) in GJB2 or OTOF genes, with and without cochlear implant (CI).
Cohort
Prospective
Pure Tone Audiometry Assessment
Other interventionCollection of Pure Tone Audiometry data performed in routine practice during study period
Quality of Life Questionnaires
Other interventionCollection of Quality of Life questionnaire's answers during study period
Audiological characteristics
Pure Tone Audiometry, thresholds on 500, 1000, 2000, 4000 Hz Speech audiometry
Electrophysiological characteristics: ABR
Auditory Brainstem Response, thresholds
Electrophysiological characteristics: OAE
Otoacoustic Emissions thresholds
Genotypic and phenotypic characterisation
Genotypic and phenotypic characterisation of the population will be assessed in Cohort 1a. Frequency of autosomal recessive 1 and 9 deafness (GJB2 and OTOF genes) and type of mutations will be evaluated among the screened population of male and female children aged \< 16 years, with a diagnosis of bilateral mild to profound, sensorineural, non-syndromic hearing loss.
Hearing-related Quality of Life questionnaire
The Hearing Environments And Reflection on Quality of Life (HEAR-QL) measurement questionnaires will be used to assess the quality of life of children. Depending on child's age, the HEAR-QL questionnaires will be completed either by parents/caregivers (child aged 2 to 6 years) either by the child (child aged 7 to 12 years). The items of the questionnaires are focused on situations affecting interactions with family and friends, participation in social and school activities, and impact of Hearing Loss on the child's emotional well being. Children/parents will be asked to rate how frequently each item was a problem for them/child in the past month using the following response choices: "never" (1), "almost never" (2), "sometimes" (3), "often" (4), or "Almost always" (5). Scores are transformed with 1=100, 2=75, 3=50, 4=25, and 5=0 points. Higher scores indicate higher perceived Quality Of Life.
