Fragile X Syndrome

Also known as: FRAXA, FXS.

What is Fragile X syndrome?

Fragile X syndrome is a genetic disorder caused by a mutation (change) on the X chromosome that affects brain development and function. It is the most common inherited cause of mental retardation (and autism). Behavior and learning challenges (children can find it hard to understand and process information), are common, and the condition occurs more frequently in boys (who tend to have a more severe intellectual disability and behavior problems ) than girls and is found in all racial and ethnic groups.

What causes Fragile X syndrome?

Fragile X syndrome occurs due to a genetic mutation on the X chromosome that prevents a protein being formed which plays an important role in the functioning of the brain. As opposed to most carriers of an abnormal gene who are generally unaffected by the mutation (silent carriers) mothers and fathers who carry a form of the gene, a “premutation” are at risk to develop Fragile X- associated disorders. A “premutation” may become unstable and become a full mutation in the child.

What are the symptoms of Fragile X syndrome?

Common symptoms of Fragile X syndrome include developmental delays, learning disabilities, speech and language problems and social, emotional and behavioral issues (hyperactivity and being shy and anxious particularly in new situations). They may also have unique physical features such as a long and narrow face, prominent ears, poor muscle tone, soft skin, flat feet, loose flexible joints, large ears and many other characteristics.

What are Fragile X syndrome care options?

As there is no cure for Fragile X syndrome, treatment is aimed at helping the children learn language and social skills. A multidisciplinary team which might include pediatric specialists in speech therapy, behavioral therapy, sensory integration occupational therapy, special education, individualized educational plans and, when necessary, treatment of physical abnormalities.

Results are better when treatment is started early.

Reviewed by: Jack Wolfsdorf MD.

This page was last updated on: October 10, 2023 05:11 PM

Pediatric Neurology

The Division of Pediatric Neurology is dedicated to the management and treatment of neurological disorders in babies, children and adolescents.

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