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Participant 098

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Female, age 36, with rapid, bilateral vocal cord spasms and muscle weakness caused by a change in the JAG1 gene

Date of Report

Aug 25, 2021


The participant was in excellent health until about three years ago when she started experiencing severe bilateral vocal cord spasms. This came on very suddenly and impacted her ability to breathe. She underwent an emergency tracheostomy and, since this procedure, her breathing has improved greatly. Over the past few years, she has also developed muscle weakness and has difficulty holding her head up. She can no longer walk long distances and has trouble getting off the ground. She has muscle twitching (fasciculations) and double vision (diplopia) as well. Recently she had an abnormal autonomic function test, which showed evidence of decreased sudomotor responses at all sites.

As a child, the participant was diagnosed with heart defects (ventricular septal defect, pulmonic stenosis), which resolved spontaneously. These heart defects are likely caused by a variant in the JAG1 gene.

Symptoms / Signs
  • Bilateral vocal cord dysfunction (spasm)
  • Non-progressive muscle weakness
  • Easy fatigability
  • Muscle twitching (fasciculations, myokymia)
  • Reduced tendon reflexes
  • Decreased lung (pulmonary) function
  • Weakness of muscles of respiration
  • Difficulty breathing (dyspnea)
  • Asthma
  • Progressive forgetfulness
  • Low blood pressure (orthostatic hypotension)
  • Abnormality of the thorax
  • Far sighted (myopia)
  • Double vision (diplopia)
  • Small distance between end of nose and upper lip (short philtrum)
  • Heart defects (ventricular septal defect, pulmonic stenosis)
  • Heart muscle disease (restrictive cardiomyopathy)
  • Short palm
  • Decreased distance between end of the finger to the crease (short distal phalanx of finger)
  • Small hand
Current Treatments
  • Trileptal, Lyrica, Mexitil – muscle twitches
Prior Treatments
  • Baclofen– muscle twitches
Considered treatments
Previously Considered Diagnoses
  • Distal myopathy with vocal cord and pharyngeal weakness
  • Finnish muscular dystrophy
  • Isaac’s disease
  • Muscular dystrophy
  • Myasthenia gravis
  • Myositis
  • Paraproteinemia
  • Parkinson’s disease
  • Pompe disease
  • Thyroid disorders
Other Photographs
Genetic Variants of Interest

In 2021, clinicians and researchers identified the following genetic change to be causing the participant’s symptoms:

Inheritance Pattern
Position (hg19)
DNA Change
Protein Change

If this participant sounds like you or someone you know, please contact us!


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