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Fragile X Syndrome

[fra-jɘl \- ‘eks-\ sin-drōm]

DNA illustration of Fragile X syndrome

Fragile X syndrome is one of the most common inherited causes of intellectual disability, which means this condition limits a person’s ability to learn at an expected level, and function in daily life . Fragile X syndrome is caused by a change in the genetic material that mostly affects brain cells. This change makes it hard for cells to produce a protein that is needed for normal brain function. Currently, there is no cure for fragile X syndrome. The sooner children are diagnosed with fragile X syndrome, the sooner they can benefit from care and services. There are behavioral treatments, medicines, and educational services that may help.


Key Facts

  • The average age at diagnosis for fragile X syndrome is 35 to 37 months for boys and 42 months for girls.
  • Learning disabilities, behavioral problems, developmental delays, and seizures are some possible symptoms of fragile X.
  • Fragile X syndrome can be an underlying cause of autism spectrum disorder.
  • Females with fragile X syndrome often have milder symptoms than males.


Prevention Tips

  • If you’re concerned about your child’s development, talk to your child’s doctor.
  • If your child has developmental or intellectual disability with no known cause, consider asking your doctor for the fragile X syndrome test, which is called the “FMR1 DNA Test for Fragile X.”
  • Currently, there is no cure for fragile X syndrome, but there are behavioral treatments, medicines, and educational services that may help your child.
  • Having a diagnosis of fragile X syndrome for your child can help you connect with support groups of other families in the same situation.
  • Tremors and early menopause are symptoms of disorders that can be related to fragile X syndrome. If you or other members of your family have these symptoms, discuss them with your doctor, even if you don’t have a family history of fragile X syndrome.

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