Genetic Analysis of Hereditary Disorders of Hearing and Balance

NCT ID: NCT00023049

Last Updated: 2026-01-05

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Total Enrollment

335 participants

Study Classification

OBSERVATIONAL

Study Start Date

2002-12-23

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

This study will try to identify the genetic causes of hereditary hearing loss or balance disorders.

People with a hearing or balance disorder that affects more than one family member may be eligible for this study. They and their immediate family members may undergo some or all of the following procedures:

* Medical and family history, including questions about hearing, balance and other ear-related issues, and review of medical records.
* Routine physical examination.
* Blood draw or buccal swab (brushing inside the cheek to collect cells) - Tissue is collected for DNA analysis to look for changes in genes that may be related to hearing loss.
* Hearing tests - The subject listens for tones emitted through a small earphone.
* Balance tests to see if balance functions of the inner ear are associated with the hearing loss In one test the subject wears goggles and watches moving lights while cold or warm air is blown into the ears. A second test involves sitting in a spinning chair in a quiet, dark room.
* Photograph - A photograph may be taken as a record of eye shape and color, distance between the eyes, and hair color.
* Computed tomography (CT) and magnetic resonance imaging (MRI) scans - These tests show the structure of the inner ear. For CT, the subject lies still for a short time while X-ray images are obtained. For MRI, the patient lies on a stretcher that is moved into a cylindrical machine with a strong magnetic field. The magnetic field and radio waves produce images of the inner ear. The radio waves cause loud thumping noises that can be muffled by the use of earplugs.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Hereditary hearing impairment is a genetically heterogeneous disorder that can be caused by mutations in any one of hundreds of different genes. Approximately 120 genes have now been identified in which mutations can cause nonsyndromic sensorineural hearing loss. The identification and analysis of these genes and their mutations are providing critical insights into the development, structure, and function of the auditory system, as well as the molecular mechanisms associated with disruption of these processes. In contrast, the molecular mechanisms underlying familial disorders affecting peripheral vestibular function appear to be more rare, have not been well described, and are less well understood. The peripheral auditory and vestibular systems share many common features in both health and disease, and many hereditary hearing loss disorders also affect vestibular function. The purpose of this study is to identify genes and mutations causing hereditary disorders of hearing, balance, or both. Members of families segregating hereditary disorders of hearing or balance will be enrolled in the proposed study in order to: (1) define and characterize the phenotypes and natural histories; (2) identify the underlying causative mutations and genes by linkage, positional cloning, and/or candidate gene mutation analyses; (3) and correlate observed phenotypes with the corresponding mutations and functions of the underlying genes.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Sensorineural Hearing Loss Hearing Disorder Vestibular Disease

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Observational Model Type

FAMILY_BASED

Study Time Perspective

PROSPECTIVE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

1

patients with known SNHL and/or peripheral vestibular dysfunction

No interventions assigned to this group

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

Persons with known SNHL and/or peripheral vestibular dysfunctions caused by genetic etiology

Family members of persons with known SNHL and/or peripheral vestibular dysfunction caused by genetic etiology

Adults must be able to provide informed consent

Minors must have a parent or guardian able to provide informed consent

Subjects must be 0-99 years of age

For Nigeria subjects with non-syndromic hearing loss, their hearing loss must be early-onset, before 10 years of age, to be eligible.

Exclusion Criteria

Persons with SNHL and/or peripheral vestibular dysfunction caused by a nongenetic etiology such as trauma, infection, metabolic or immunologic disorders, or exposure to ototoxic agents such as noise or aminoglycoside antibiotics will not be included in this protocol.
Maximum Eligible Age

99 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

National Institute on Deafness and Other Communication Disorders (NIDCD)

NIH

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Thomas B Friedman, Ph.D.

Role: PRINCIPAL_INVESTIGATOR

National Institute on Deafness and Other Communication Disorders (NIDCD)

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

National Institutes of Health Clinical Center

Bethesda, Maryland, United States

Site Status

Institute of Child Health, College of Medicine, University of Ibadan

Ibadan, , Nigeria

Site Status

Countries

Review the countries where the study has at least one active or historical site.

United States Nigeria

References

Explore related publications, articles, or registry entries linked to this study.

Cohn ES, Kelley PM, Fowler TW, Gorga MP, Lefkowitz DM, Kuehn HJ, Schaefer GB, Gobar LS, Hahn FJ, Harris DJ, Kimberling WJ. Clinical studies of families with hearing loss attributable to mutations in the connexin 26 gene (GJB2/DFNB1). Pediatrics. 1999 Mar;103(3):546-50. doi: 10.1542/peds.103.3.546.

Reference Type BACKGROUND
PMID: 10049954 (View on PubMed)

Griffith AJ, Friedman TB. Making sense out of sound. Nat Genet. 1999 Apr;21(4):347-9. doi: 10.1038/7668. No abstract available.

Reference Type BACKGROUND
PMID: 10192378 (View on PubMed)

Morton NE. Genetic epidemiology of hearing impairment. Ann N Y Acad Sci. 1991;630:16-31. doi: 10.1111/j.1749-6632.1991.tb19572.x. No abstract available.

Reference Type BACKGROUND
PMID: 1952587 (View on PubMed)

Related Links

Access external resources that provide additional context or updates about the study.

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

01-DC-0229

Identifier Type: -

Identifier Source: secondary_id

010229

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.

Genetics of Middle Ear Disease
NCT00422136 COMPLETED
Genetic Component of Handedness
NCT00005003 COMPLETED
Genetic Studies of Lysosomal Storage Disorders
NCT00001215 ENROLLING_BY_INVITATION