Epidemiology of Non-syndromic Dominant Deafness (SURDOM)

Genetic Epidemiology of Non-syndromic Dominant Deafness

Hearing impairment is a common disorder that affects at least 7% of individuals in our countries. Even the causes of hearing impairment are numerous, genetic causes represent the main factor of sensorineural deafness. Among hereditary non-syndromic deafness autosomal-dominant inheritance is observed in about 10-20% of the cases. These forms of deafness are usually post-lingual and progressive. To date more than 41 chromosomal localisation and 21 genes associated to non syndromic dominant deafness have been described. It represents an extreme genetic heterogeneity making difficult the studies of these forms of hearing impairment. But, genetic diagnostic testing is crucial in these cases. Indeed, therapeutic research are in the way to prevent the progression of the disorder. The aim of this work is to establish the prevalence of the different genes involved in these forms of deafness.

Study Overview

• Status: Completed
• Conditions: Hearing Impairment
• Intervention / Treatment: Biological: blood sample

Detailed Description

The protocol consists first in the recruitment of 150 families with non syndromic dominant hearing impairment. The families will be recruited by the clinical investigators. The clinic and radiological characteristics of the hearing impairment will be collected by the clinical investigators. Samples of patients and healthy relatives will be sent to the referral center. A linkage study of the whole genome by SNP studies is in progress in a cohort of large families affected by autosomal dominant deafness. This work will enable us to select the loci that may be frequently implicated in our population and screen these genes in the 150 families included in the protocol.

• Study Type: Observational
• Enrollment (Actual): 183

Contacts and Locations

Study Locations

• France
  • Paris, France, 75012
    • Hôpital Armand-Trousseau, Service d'ORL pédiatrique et de Chirurgie Maxillo Faciale

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 4 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

families with non syndromic dominant hearing impairment followed by the clinical investigators

Description

Inclusion Criteria:

• Age > 4 years.
• Patient presenting familial dominant non syndromic hearing loss starting between 4 and 40 years old, over 2 generations
• Healthy volunteer from the same families
• Clinical and paraclinical assessment (genetic and ophthalmologic examination, audiometric tests, inner ear CT scan)
• Affiliated to the national health insurance benefit
• Signature of informed consent form

Exclusion Criteria:

• hearing loss resulting from an extrinsic reason or an associated syndrome
• Defective or insufficient samples
• No or insufficient clinical and biological description
• No informed consent form

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Cross-Sectional

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
1; Patient presenting familial dominant non syndromic hearing loss starting between 4 and 40 years old, over 2 generations	Biological: blood sample; Peripheral whole blood sample, 5 ml
2; Healthy volunteer from the same families	Biological: blood sample; Peripheral whole blood sample, 5 ml

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
The identification of a deleterious mutation of a gene coding a protein present in the cochlea	1 day

Secondary Outcome Measures

Outcome Measure	Time Frame
The phenotype genotype relationships after identification of the causative gene and mutation	1 day

Collaborators and Investigators

• Sponsor: Assistance Publique - Hôpitaux de Paris
• Investigators: Principal Investigator: Françoise Denoyelle, MD, PhD, Assistance Publique - Hôpitaux de Paris

Study record dates

Study Major Dates

• Study Start: April 1, 2009
• Primary Completion (Actual): April 1, 2012
• Study Completion (Actual): April 1, 2012

Study Registration Dates

• First Submitted: March 29, 2010
• First Submitted That Met QC Criteria: June 23, 2010
• First Posted (Estimate): June 24, 2010

Study Record Updates

• Last Update Posted (Estimate): August 7, 2013
• Last Update Submitted That Met QC Criteria: August 6, 2013
• Last Verified: August 1, 2013

More Information

Terms related to this study

• Keywords: Prevalence; Mutation; Autosomal dominant inheritance
• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Otorhinolaryngologic Diseases; Ear Diseases; Sensation Disorders; Hearing Disorders; Hearing Loss; Deafness
• Other Study ID Numbers: AOM 08041