Genetic Analysis of Human Hereditary Hearing Impairment
Data Collection
Ear Diseases+6
+ Hearing Disorders
+ Nervous System Diseases
Summary
Study start date: September 8, 1997
Actual date on which the first participant was enrolled.The objective of this research project is to map and clone genes that are important for the normal development or maintenance of the auditory system. One strategy for identifying some of the genes important for auditory processes is to ascertain large families each with several hearing impaired individuals. Initial contact will be made by family physicians, audiologist, supervisors in schools for the hearing impaired, and directly by the principal investigators during surveys of schools for the deaf and visits with hearing impairment self-help groups. Members of a family will be evaluated by an audiologist, and instances of hearing impairment will be documented and categorized. A clinician would then examine hearing impaired and unaffected members of the family for the presence of other clinical features so as to distinguish between nonsyndromic and syndromic forms of hearing impairment. Pedigrees of these families will be analyzed to determine the mode of inheritance of the hereditary hearing impairment segregating in each family. Families will be ascertained through audiologists and other clinicians, genetics clinics, schools for the hearing impaired and through linguists and medical anthropologists who study unique sign languages and the sociology of communities with a high proportion of hearing impaired individuals. The mutated gene will then be genetically mapped by a linkage or association based strategy, using DNA typing of highly polymorphic genetic markers distributed across the human genome.
Protocol
This section provides details of the study plan, including how the study is designed and what the study is measuring.404 patients to be enrolled
Total number of participants that the clinical trial aims to recruit.Eligibility
Researchers look for people who fit a certain description, called eligibility criteria: person's general health condition or prior treatments.Any sex
Biological sex of participants that are eligible to enroll.Healthy volunteers not allowed
If individuals who are healthy and do not have the condition being studied can participate.Conditions
Pathology
Criteria
INCLUSION CRITERIA: It is anticipated that, in most cases, patients will be recruited whose disorders do not appear to be syndromic (i.e. are not associated with extra-auditory or extra-vestibular features). We seek subjects who are members of large families with multiple individuals affected with a hearing disorder. Sporadic cases will occasionally be included when the phenotype has features suggestive of mutations in one or a few particular candidate genes, since autosomal or X-linked recessive inheritance can appear to be sporadic. If there is evidence of genetic homogeneity, small families can be pooled for linkage analysis, or a combination of large and small families can be pooled. Subjects of any ethnic background, gender, age, sexual orientation, or health status will be included. EXCLUSION CRITERIA: Patients will be excluded when their hearing or vestibular dysfunction are known to be caused by a nongenetic etiology such as trauma, infection, metabolic or immunologic disorders, or exposure to ototoxic agents such as noise or aminoglycoside antibiotics.
Study Centers
These are the hospitals, clinics, or research facilities where the trial is being conducted. You can find the location closest to you and its status.This study has 1 location
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, United StatesOpen National Institutes of Health Clinical Center, 9000 Rockville Pike in Google Maps