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Characteristics of Idiopathic Familial Voice Disorders

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00001552
Recruitment Status : Completed
First Posted : November 4, 1999
Last Update Posted : July 2, 2017
Information provided by:
National Institutes of Health Clinical Center (CC)

Brief Summary:

The purpose the study is to determine the genetic causes of specific voice disorders that run in families. Researchers are particularly interested in two conditions;

  1. Spasmodic dysphonia
  2. Vocal fold paralysis

Familial vocal fold paralysis can be a life-threatening disorder that can cause difficulty with vocal fold movement for breathing and voice and sometimes for swallowing. Studies are ongoing at the NIH to better understand the pathophysiology and to relate it to the genetic pattern of inheritance. Families are being recruited to participate in these studies and are being provided with further information on the disorder and genetic counseling if desired. Physician referral is requested for affected members of families with vocal fold paralysis of an unknown cause occurring over at least 2 generations. All travel, lodging, examination and counseling costs are covered for both affected and unaffected members of a family. Examinations include: voice, laryngeal, neurological, electrodiagnostic testing, genetic counseling, and radiological studies....

Condition or disease
Laryngeal Disease Spastic Dysphonia Voice Disorder

Detailed Description:


Our purpose is to examine for evidence of genetic risk factors associated with idiopathic laryngeal motor control disorders. During the conception of the protocol, we were interested in investigating the pattern of inheritance of familial voice disorders, specifically spasmodic dysphonia and tremor. Interestingly, the initial search for families revealed several large families with idiopathic vocal fold paralysis with some family members experiencing symptoms of spasmodic dysphonia. During subsequent years, the research has focused on inherited forms of vocal fold paralysis in an attempt to determine the relationship between the laryngeal motor control disorder and other associated neuropathies, and to determine the existence of a specific genetic abnormality. These idiopathic laryngeal motor control disorders were one manifestation of peripheral neuropathies or may be an isolated disorder with only laryngeal involvement. Subsequently, we have shifted our emphasis back to the identification of genetic risk factors for spasmodic dysphonia.

Hypothesis 1) Familial risk factors for spasmodic dysphonia result in a particular phenotype and genotype.

Hypothesis 2) Environmental risk factors may differentiate between affected and unaffected members of families with spasmodic dysphonia.

Hypothesis 3) Whole genome screening will identify SNPs associated with the occurrence of spasmodic dysphonia.


Families with multiple members affected with spasmodic dysphonia, vocal fold paralysis, and tremor will be ascertained.


A pedigree will be developed via a questionnaire and voice history. Affected and unaffected family members will be examined to determine the presence and extent of their laryngeal motor control disorder. Affected family members will also undergo neurological examination and nerve and muscle studies to determine the loci of their pathology. A genotype will be developed for affected and unaffected family members, through DNA testing of blood samples.


This is a natural history study characterizing the phenotype and genotype of idiopathic laryngeal motor control disorders.

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Study Type : Observational
Enrollment : 270 participants
Official Title: Characteristics of Idiopathic Familial Voice Disorders
Study Start Date : May 22, 1996
Actual Primary Completion Date : November 13, 2009

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Voice Disorders

Information from the National Library of Medicine

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Ages Eligible for Study:   Child, Adult, Older Adult
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Symptoms present during speech and not apparent at rest,

Symptoms less evident during whisper, singing or falsetto.

Symptoms become worse with prolonged speaking, practice or anxiety.

Reflexive and emotional aspects of voice function are unaffected, such as coughing, laughter or crying.


Any patient with a history of airway obstruction will be excluded from the study.

Structural abnormalities affecting the larynx such as vocal fold nodules, polyps, carcinoma, cysts, contact ulcers, or inflammation (laryngitis).

Reduction in vocal fold movement range during non-speech tasks such as whistling which would suggest either paralysis or paresis, joint abnormality or neoplasm.

No smokers or tobacco users will be included in the study.

Subjects with history of a psychiatric disorder, under the care of a psychiatrist, or on medications for treatment of a psychiatric disorder will be excluded from the study. Examples of psychiatric disorders to be excluded are: somatoform disorders, conversion disorders, currently under treatment for a major depression, or a history of schizophrenia or a bipolar disorder. However, a history of a previous episode of a minor reactive depression would not exclude a person from participation.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00001552

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United States, Iowa
University of Iowa
Iowa City, Iowa, United States, 52242
United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
United Kingdom
Kennedy-Galton Centre Medical & Community Genetics
Harrow, United Kingdom
Institute of Cancer Research
Sutton, United Kingdom
Sponsors and Collaborators
National Institute of Neurological Disorders and Stroke (NINDS)

Layout table for additonal information Identifier: NCT00001552     History of Changes
Other Study ID Numbers: 960089
First Posted: November 4, 1999    Key Record Dates
Last Update Posted: July 2, 2017
Last Verified: November 13, 2009

Keywords provided by National Institutes of Health Clinical Center (CC):
Spasmodic Dysphonia
Vocal Fold Paralysis
Voice Disorder

Additional relevant MeSH terms:
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Voice Disorders
Laryngeal Diseases
Pathologic Processes
Respiratory Tract Diseases
Otorhinolaryngologic Diseases
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms
Respiration Disorders
Signs and Symptoms, Respiratory