Also called: FRAXA · FXS
Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
About Fragile X Syndrome
Fragile X syndrome is the most common form of inherited developmental disability. A problem with a specific gene causes the disease. Normally, the gene makes a protein you need for brain development. But the problem causes a person to make little or none of the protein. This causes the symptoms of Fragile X.
People with only a small change in the gene might not show any signs of Fragile X. People with bigger changes can have severe symptoms. These might include:
- Intelligence problems, ranging from learning disabilities to severe intellectual disabilities
- Social and emotional problems, such as aggression in boys or shyness in girls
- Speech and language problems, especially in boys
A genetic blood test can diagnose Fragile X. There is no cure. You can treat some symptoms with educational, behavioral, or physical therapy, and with medicines. Getting treatment early can help.
It sits within Genetics/Birth Defects.
The lead U.S. institute for this subject is the Eunice Kennedy Shriver National Institute of Child Health and Human Development.
When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.
Research on Fragile X Syndrome
121 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.
What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.
Research currently under way
- Study of MRM-3379 in Male Participants With Fragile X Syndrome (BLOOM)Mirum Pharmaceuticals, Inc.
- Sertraline vs. Placebo in the Treatment of Anxiety in Children and AdoLescents With NeurodevelopMental DisordersHolland Bloorview Kids Rehabilitation Hospital
- Safety, Tolerability, and Preliminary Effectiveness of CTH120 in Fragile X SyndromeConnecta Therapeutics, S.L.
- Web Intervention for Parents of Youth With Genetic Syndromes (WINGS)Rush University Medical Center
- Parent and Infant Inter(X)Action Intervention (PIXI)RTI International
- Tracking Early Emergence of Sound Perception Impairments in FXS With Multimodal fNIRS/EEG- InfantChildren's Hospital Medical Center, Cincinnati
Research already completed
- A Study of BPN14770 in Male Adults (Aged 18 to 45) With Fragile X SyndromeTetra Discovery Partners
- Study of SPG601 in Adult Men With Fragile X SyndromeSpinogenix
- A Randomized Study of BPN14770 in Male Adolescents (Aged 9 to < 18 Years) With Fragile X SyndromeTetra Discovery Partners
Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.
Where to read more
Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.
Start Here
- About Fragile X SyndromeCenters for Disease Control and Prevention
- About Fragile X SyndromeNational Human Genome Research Institute
- Fragile X SyndromeEunice Kennedy Shriver National Institute of Child Health and Human Development
- Fragile X-Associated Disorders (FXD): A Handbook for Families, Health Care Providers, Counselors, and EducatorsNational Fragile X Foundation
Symptoms
- Fragile X 101National Fragile X Foundation
- What Are the Symptoms of Fragile X Syndrome?Eunice Kennedy Shriver National Institute of Child Health and Human Development
Diagnosis and Tests
- How Do Health Care Providers Diagnose Fragile X Syndrome?Eunice Kennedy Shriver National Institute of Child Health and Human Development
Treatments and Therapies
- What Are the Treatments for Fragile X Syndrome?Eunice Kennedy Shriver National Institute of Child Health and Human Development
Related Issues
- About Fragile X-Associated Primary Ovarian Insufficiency (FXPOI)Eunice Kennedy Shriver National Institute of Child Health and Human Development
- Autism (and Fragile X Syndrome)National Fragile X Foundation
- Fragile X-Associated Tremor and Ataxia Syndrome (FXTAS)Eunice Kennedy Shriver National Institute of Child Health and Human Development
- Other Fragile X Syndrome FAQsEunice Kennedy Shriver National Institute of Child Health and Human Development
Genetics
- Fragile X PremutationNational Fragile X Foundation
- Fragile X syndrome: MedlinePlus GeneticsNational Library of Medicine
Clinical Trials
- ClinicalTrials.gov: Fragile X SyndromeNational Institutes of Health
Medical subject headings
Clinicians and researchers index this subject under Fragile X Syndrome. These are the terms to use when searching medical literature.
This page is built from the MedlinePlus health topic record for Fragile X Syndrome, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.