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FXTAS

FXTAS, or fragile X-associated tremor/ataxia syndrome, is one of three known Fragile X-associated Disorders (FXD). All the FXD are caused by changes in the FMR1 Gene.

What Is FXTAS?

FXTAS is an “adult onset” neurodegenerative disorder, occurring more commonly in males than females. Onset is usually over 50 years of age, and most individuals had no related medical, developmental or neurological problems prior to the appearance of FXTAS symptoms. Females comprise only a small part of the FXTAS population, and their symptoms tend to be less severe.

What Are the Symptoms of FXTAS?


The features of FXTAS include:

  • Ataxia (balance problems).
  • Intention tremors (during intentional movement such as pouring, writing, etc,).
  • Memory loss (usually short-term).
  • Mood instability, irritability, personality change, psychiatric symptoms.
  • Parkinson’s symptoms (many individuals will be misdiagnosed with Parkinson’s Disease” prior to diagnosis of FXTAS).
  • Dementia (many individuals will be misdiagnosed with Alzheimer’s disease prior to diagnosis FXTAS).
  • Cognitive decline (loss of math, reading, and verbal comprehension skills).
  • FXTAS progresses at varying rates in different individuals.

What Causes FXTAS?

FXTAS is caused by a change or mutation in a gene called the FMR1 gene. All individuals with FXTAS have what is called an FMR1 premutation. Men with FXTAS inherited this genetic change from their mother, women with FXTAS can inherit it from their mother or father.

Can You Pass FXTAS on to Your Children?

Anyone with an FMR1 premutation can pass the gene mutation on to their children. Not everyone with the FMR1 mutation will get FXTAS. Males with the FMR1 premutation will pass it on to all their daughters and none of their sons. Females with the premutation will have a 50/50 chance in each pregnancy to pass it on to children of both genders. Women with the premutation can potentially have children with fragile X syndrome.

How Is FXTAS Diagnosed?

FXTAS is usually diagnosed by a neurologist, a specialist in movement disorders, a geneticist, or psychiatrist. Individuals who exhibit any FXTAS symptoms, whether they are known to be FMR1 carriers or not, should be evaluated by one of these specialists.

For More Information

Call or email the National Fragile X Foundation (800) 688-8765 or natlfx@fragilex.org and ask for a FXTAS packet. Also, visit our website at www.fxtas.org.