What is FXTAS? | Is there a test?  | FXTAS symptoms |   
Treatment | Female Occurence

What Is FXTAS?

Carriers of premutation (CGG) expansions of the fragile X gene are generally thought to be spared most of the problems associated with the full mutation; however, a newly identified neurological disorder, involving progressively and difficulty with walking and balance, appears to specifically affect some older premutation carriers, generally grandfathers of children with fragile X syndrome. Although this neurological disorder occurs by a completely separate mechanism from fragile X syndrome—and affects different individuals, it is caused by the same gene, and therefore opens a new portal for understanding how the fragile X gene works.

Is there a test?

Yes, it is the same DNA test used to diagnose fragile X syndrome. So an adult physician would simply order the DNA test for the fragile X (FMR1) gene.

What are the symptoms of FXTAS?

FXTAS has multiple symptoms. Some patients develop all of them, others only a few. The average age of onset is 60. A common early symptom is tremor in the arms during action; this progresses and may eventually hinder eating and handwriting.

Another frequent symptom is balance difficulty and poor coordination (ataxia). The usual walk may look drunken, with staggering or leaning to one side. Some men have falls for unclear reasons or easily trip over objects they would formerly have stepped over with ease. The ability to stand on one foot or to stand with one foot straight in front of the other, touching toe to heel, is gradually lost.

Some affected men look like they are developing Parkinson’s disease, with generalized slowness, stiffness and decreased facial expression.

Cognitive and psychological changes are less obvious than the motor symptoms (tremor, ataxia, parkinsonism), though for many people, they may be more problematic. The degree and type of these problems may vary considerably among affected persons. Difficulty with short-term memory is common and occurs early in the syndrome.

Other symptoms include slowed thought, reduced ability to actively problem-solve or to deal with complex and new tasks. The general intellectual decline over time often results in dementia (severe thinking problems) in the late stages. These changes often affect personality. Psychological changes include depression and anxiety, but impatience, hostility, and moodiness may be common. It is not unusual for men with FXTAS to become impulsive, doing things that are inappropriate or irrelevant to the situation at hand. It also may become difficult for them to take initiative on and complete everyday tasks. Affected men are usually unaware they are developing these signs, and may even deny them when confronted by relatives and other people.

Back to Top of Page

Is there a medication that helps diminish tremors in FXTAS patients?

Although there is no specific treatment for the tremor or balance problems associated with FXTAS, there are several classes of medications, currently available to treat similar symptoms in other disorders, which may provide some benefit. However, additional treatment studies are needed at this point. Individuals with FXTAS should discuss treatment options with their physician.

How common is FXTAS in female carriers?

Although FXTAS has now been shown to occur in a small fraction of female carriers the exact numbers are not yet known. We do not yet understand why relatively few female carriers develop FXTAS. One reason may be the milder symptoms experienced by some females, but many others don’t seem to have any problems.