Genetic Analysis of Hereditary Disorders of Hearing and Balance
2 other identifiers
observational
335
2 countries
2
Brief Summary
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.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for all trials
2 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
August 21, 2001
CompletedFirst Posted
Study publicly available on registry
August 22, 2001
CompletedStudy Start
First participant enrolled
December 23, 2002
CompletedApril 24, 2026
February 23, 2026
August 21, 2001
April 23, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
To define and characterize the phenotypes and natural histories of families with segregating hereditary disorders of balance or hearing and to identify the possible mutations and genes by genetic analysis
Characterize the natural history of hereditary disorders affecting hearing and/or balance Identify the genes, including both known and as yet undiscovered genes, that can cause hereditary disorders of hearing or balance Identify and characterize the structure and functions of these genes in the development and function of the peripheral auditory and vestibular systems Determine how mutations in these genes cause hearing loss and vestibular dysfunction Correlate genotypes and phenotypes to identify clinical features that may be used to facilitate the genetic diagnosis of hereditary disorders affecting hearing or balance
Ongoing
Study Arms (1)
1
patients with known SNHL and/or peripheral vestibular dysfunction
Eligibility Criteria
We will be studying up to 750 people with hearing losses or balance problems that are thought to be hereditary and, if possible, their family members, either with or without hearing or balance problems to participate in our study. A total of up to 400 affected and unaffected individuals, including family members and control subjects will be enrolled from the Nigerian population.
You may qualify if:
- 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.
You may not qualify if:
- 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.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (2)
National Institutes of Health Clinical Center
Bethesda, Maryland, 20892, United States
Institute of Child Health, College of Medicine, University of Ibadan
Ibadan, Nigeria
Related Publications (3)
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.
PMID: 10049954BACKGROUNDGriffith AJ, Friedman TB. Making sense out of sound. Nat Genet. 1999 Apr;21(4):347-9. doi: 10.1038/7668. No abstract available.
PMID: 10192378BACKGROUNDMorton 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.
PMID: 1952587BACKGROUND
Related Links
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
Thomas B Friedman, Ph.D.
National Institute on Deafness and Other Communication Disorders (NIDCD)
Study Design
- Study Type
- observational
- Observational Model
- FAMILY BASED
- Time Perspective
- PROSPECTIVE
- Sponsor Type
- NIH
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
August 21, 2001
First Posted
August 22, 2001
Study Start
December 23, 2002
Last Updated
April 24, 2026
Record last verified: 2026-02-23