The genetic disorder Fragile X syndrome, which results from mutations in a gene on the X chromosome, is the most commonly inherited form of developmental and intellectual disability.
NICHD supports and conducts research on the diagnosis, treatment, management, prevention, and inheritance of Fragile X and its associated conditions, Fragile X-Associated Primary Ovarian Insufficiency (FXPOI) and Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS). All three conditions result from changes in the same gene on the X chromosome.
Fragile X syndrome is a genetic disorder that affects a person’s development, especially that person’s behavior and ability to learn.
The mutation in the FMR1 gene affects how the body makes the Fragile X Mental Retardation Protein. This causes the body to make little or none of the protein, which can cause the Fragile X symptoms.
Fragile X results from a change or mutation in the Fragile X Mental Retardation 1 (FMR1) gene, which is found on the X chromosome.
People with Fragile X have some symptoms in common, including intellectual problems, physical features unique to this syndrome, behavioral challenges, speech and language problems, and sensory issues.
Healthcare providers often use a blood sample to diagnose Fragile X. They will take a sample of blood and will send it to a laboratory, which will determine what form of the FMR1 gene is present.
Individuals with Fragile X who receive appropriate education, therapy services, and medications have the best chance of using all of their individual capabilities and skills.
Most children with Fragile X can benefit from special education services that are tailored to their particular strengths and challenges.
Those with Fragile X might benefit from services provided by different specialists, including speech-language therapists, occupational therapists, physical therapists, and behavioral therapists.
Find answers to other common questions about Fragile X syndrome, such as conditions associated with Fragile X syndrome, how it is inherited, and how the genetic mutation occurs.