Fragile X-Associated Tremor & Ataxia Syndrome (FXTAS) Overview

Fragile X-associated tremor and ataxia syndrome (FXTAS) is a late-onset condition (occurs in people older than age 50) that develops in some men and women with an altered form of the fragile X gene. Those with FXTAS do not have the intellectual or developmental disabilities common in fragile X syndrome.
NICHD-supported researchers were the first to identify FXTAS and link it to changes in the FMR1 gene, which causes fragile X syndrome. The Institute is one of several federal agencies working to understand FXTAS and other conditions caused by changes in the FMR1 gene.
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Fast Facts

Common Name

Fragile X-associated tremor and ataxia syndrome (FXTAS)

Medical or Scientific Name

FXTAS (pronounced FAX-tass)

Causes

FXTAS occurs in some individuals with minor changes in the FMR1 gene called a premutation. Scientists are currently exploring why some individuals with the premutation have symptoms of FXTAS while others do not. More extensive changes in FMR1 lead to fragile X syndrome. Individuals with fragile X syndrome are not at risk for FXTAS.

Number of People Affected

After age 50, about 30% to 40% of men and 8% to 16% of women with the genetic change in the FMR1 gene that leads to FXTAS will develop some symptoms of FXTAS.

Common Symptoms

Men with FXTAS have symptoms that include tremors when making movements; balance problems; symptoms similar to Parkinson's disease, such as muscle stiffness and rigidity; difficulty in making decisions; memory loss; numbness in hands and feet; and personality and mood changes. Women with FXTAS experience similar symptoms, but the symptoms may be less severe and may include other features, such as muscle pain and thyroid problems.

Common Treatments

Certain medications and therapies are helpful for treating some of the symptoms of FXTAS. However, none of these treatments can stop FXTAS from progressing, and none is considered a cure.