Kearns-Sayre Syndrome

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Kearns-Sayre Syndrome

• Charles Shepherd
• Bio 313

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Background

• Rare neuromuscular disorder
• Only 226 cases reported in literature
• Effects mitochondria
• Large duplications or deletions in mitochondrial
  DNA (gt1000bp) results in under or over production
  of mitochondrial gene products
• 1/3 cases 4977bp deletion
• Randomly effects people
• only isolated reports of any kind or inheritance
  pattern
• Prognosis
• Depends on severity
• Severe cases 85 muscle mitochondrial genome
  affected

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Symptoms

• Onset before 20 and includes
• Immobile or limited eye movement
• Abnormal pigment in eyes
• Cardiac problems or congestive heart failure
• Muscle and skeletal weakness
• Short stature
• Hearing
• Ataxia (coordination problems)
• Diabetes
• Dementia and other mental illnesses
• Affects systems with higher energy requirements
  most

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Diagnosis

• Southern Blots using samples taken from affected
  tissue
• Isolate mitochondrial DNA from affected tissue
• 16.5 kb normal
• Additional larger or smaller bands found by
  probes duplication or deletion
• Accumulation of symptoms
• Check the protein and lactate levels in the
  cerebrospinal fluid
• if present, the levels are elevated.

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Treatment

• Supportive
• Syndrome becomes worse with time
• inevitably fatal
• Symptomatic
• Heart
• Muscle
• Hearing
• Diabetes
• Vision
• Drugs

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Noticed Anomalies in lab studies

• Changes in grey and white matter levels in
  various parts of the brain
• Many help explain dementia seen in some
  individuals
• Abnormally large irregularly shaped mitochondria
  in heart and skeletal muscle

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References

• http//www.ninds.nih.gov/disorders/kearns_sayre/ke
  arns_sayre.htm
• http//www.emedicine.com/ped/topic2763.htm
• Pasternak, J. J. An Introduction to Human
  Molecular Genetics Mechanisms of Inherited
  Diseases. 2nd ed. New Jersey Wisley, 2005.