Fragile X syndrome

Fragile X syndrome, sometimes referred to as Martin-Bell syndrome, includes a spectrum of disabilities, including emotional, physical, intellectual and behavioral symptoms. This syndrome involves a mutation of the X chromosome which causes abnormal neural developement.

Symptoms of Fragile X Syndrome

Fragile X syndrome is more commonly diagnosed in males than in females. This condition varies from mild to severe and causes a wide array of symptoms. Following is a list of characteristics that may affect a patient both physically and non-physically:

  • Large and elongated face
  • Large ears
  • Flat feet
  • Enlarged testes
  • Low muscle tone
  • Social anxiety
  • Avoidant behavior
  • Inability to recognize familiar faces
  • Hyperactivity
  • Anxiety
  • Tremor
  • Dementia
  • Symptoms of autism
  • Memory problems
  • Poor communication skills
  • Self-talk
  • Repetition in speech, movement and actions
  • Lazy eye

Causes of Fragile X Syndrome

Fragile X syndrome is caused by a genetic mutation of the FMR1 gene in the X chromosome. The involvement of this chromosome is thought to be part of the reason that males are affected more often than females. Men have only one copy of the X chromosome, while women have two, leading to the theory that one is often used as a backup copy in females. Since males pass a Y chromosome on to their sons, this syndrome will not be passed to male children, but will always be passed to daughters through the mutated X chromosome. Specifically, the FMR1 gene varies in length from person to person and creates a range of number repetitions called a CGG repeat. When the number of times this pattern is repeated is very low, symptoms of this syndrome will be present.


There are currently a couple of ways to test for Fragile X syndrome when symptoms indicate this genetic disability may be present. The Southern blot analysis is used to detect a specific DNA sequence and the use of restriction enzyme digestion helps to manipulate and modify DNA for investigation. There are a number of circumstances that may cause a professional to recommend testing. Children who are directly experiencing symptoms, and adults with a family history of this syndrome could benefit from the discovery of testing results. Similarly, adults over the age of 50 who experience tremors, balance disorders or undiagnosed symptoms of Parkinson's disease may be carriers of the mutated gene.

Treatment Options for Fragile X Syndrome

Because there is no cure for Fragile X syndrome, treatment options are aimed at preventing future transmission by recommending genetic counseling and minimizing symptoms. This is usually accomplished with several types of therapy and social services. Depending upon the severity of symptoms and the age of the patient, certain types of therapy may be more beneficial than others:

  • Medication - there are no medications recommended specifically for direct treatment of Fragile X syndrome, but there are many different drugs that may be effective in treating symptoms. For example, if a particular patient has trouble with severe anxiety or social phobias, anti-anxiety medication may be beneficial.
  • Speech therapy - when language and communication are affected by physical symptoms, as well as attention problems, behavioral characteristics and oral-motor skills, speech and language therapy may be recommended, especially for younger patients.
  • Behavioral therapy - calming techniques, modification of environment, social intervention and encouragement of certain activities can benefit a patient with this condition. Behavioral therapy often offers exercises and advice on how to prevent certain behaviors with awareness of triggers, distraction techniques and specialized activities.
  • Cognitive development therapy - early intervention with stimulation for increased learning has been shown to be very effective.
  • Occupational therapy - trained professionals in this area can provide help for problematic arousal levels, fine motor skill weaknesses and sensory disorders. These types of therapists often recommend ways for patients to perform activities and advance in skills using various behavioral patterns and exercises.