Fragile X

Fragile X syndrome (FXS) is the most common form of hereditary mental retardation. FXS is an X-linked dominant genetic disorder with features that vary from person to person with FXS.

Physical: Non-Physical:

Large ears
Long, narrow face
Prominent forehead
Prominent, square chin
Large testicles
High palate (roof of mouth)
Mitral valve prolapse (leaky heart valve)
Eye problems

Developmental delay
Moderate to severe mental retardation
Learning disabilities
Autistic-like features:

  • Hand biting
  • Hand flapping
  • Poor eye contact
  • Shyness
  • Social anxiety
Mental health issues
Difficulty adjusting to change

(From the National Fragile X Foundation Handbook for families and professionals)

Both males and females can be affected with FXS; however, because the gene is on the X-chromosome, more males are affected than females. As many as 1 in 4000 males and 1 in 8000 females have this syndrome. In the general population, approximately 1 in 300 women are carry the fragile X premutation, the form of the gene that can change to the full mutation when passed from mother to child. The full mutation can lead to FXS.

Resources for families

You can help by participating in our studies

 This portion of the website is under construction. Please check back for current Emory Fragile X Center studies.

Resources for Families and Professionals

The National Fragile X Foundation

The NFXF has patient friendly information that can be obtained from their website at or by calling (800)688-8765. The organization hosts a yearly international conference for families and professionals.

Specialty Clinic

Our Fragile X Syndrome Clinic provides services for individuals from birth to 18 years of age. The Fragile X clinic is part of the Emory Fragile X Center, which also focuses on education and research. The center is currently conducting several fragile X clinical trials.  For more information please call: 404-778-1363.