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4H Syndrome

What is 4H syndrome?

4H stands for hypomyelination (lack of myelin), hypogonadotropic hypogonadism (the central nervous system does not initiate normal puberty development), and hypodontia (missing teeth). This condition is a subtype of leukodystrophy

What are the symptoms of 4H syndrome?

Symptoms are not present at birth or during the first year of life. When symptoms do appear, they include: 

  • Ataxia (progresses slowly over time)
  • Speech difficulties
  • Seizures
  • Stiff muscles
  • Delayed milestones, like walking
  • Seizures 
  • Myopia
  • Lack of puberty
  • Some teeth present at birth
  • Short stature
  • Abnormalities of the teeth

What causes 4H syndrome?

A mutation in one of three genes causes this syndrome: POL3RA, POL3RB and POLR1C. All of these genes are inherited in an autosomal recessive pattern. 

How is 4H syndrome diagnosed?

Doctors typically suspect 4H syndrome after noticing the characteristic symptoms, usually ataxia and teeth abnormalities. An MRI will be used, and genetic testing can confirm a diagnosis. 

What are the treatments for 4H syndrome?

Treatment is symptomatic and will most likely require a team of specialists. 

Where can I find out more about 4H syndrome?

4H Syndrome Articles