What is Fragile X Syndrome?

The most common signs of Fragile X syndrome, also referred to as Martin-Bell syndrome or Escalante's syndrome, include hand flapping, sensory defensiveness, and impulsive behavior. Fragile X is a family of genetic conditions all caused by gene changes in the FMR1 gene. It can be diagnosed with genetic testing and currently Fragile X is considered to be one of the most common causes of hereditary mental impairment and the only known cause of autism.

Gene carriers can be male ( 1 out of 4000) or female (1 out of 6000) and although they may not display associated characteristics they are at risk of having children or offspring with the genetic condition. There may be multiple individuals affected in one family or after generations one individual may suddenly be the first family member to show evidence of the genetic disorder.

Fragile X is diagnosed with a blood test, which should be considered for any individual that is showing signs of autism or other pervasive developmental disorders. I am not sure how often doctors are recommending this test be done before making a diagnosis of autistic disorder, but I am concerned that it may be under-diagnosed and contributing to the recent rise in prevalence rate.

Fragile X Syndrome portrays the following characteristics:

  • Physical Features: Flexible joints, large/protruding ears, low muscle tone, long face, large testicles in males, seizure disorders, soft skin, and recurrent otitis media in childhood.
  • Behavioral, Intellectual and Social Characteristics: Impulsivity, poor eye contact, autism spectrum disorders, ADHD symptoms, Hand-flapping, hand biting, tactile defensiveness and sensory overload, cognitive impairment, and speech, language and motor delays.
  • Difficulties for Adults: Transitions to new environments (e.g. schools and jobs), Learning adult activities of daily living (e.g. money concepts and transportation), managing emotions without aggression, and making/keeping friendships.
  • Challenges for Females: Visual and spatial challenges (e.g. reading maps and graphs), mathematics, social anxiety and shyness, poor communication abilities, difficulty noticing social cues, mood swings, and depression.
  • Presence of Positive Family History: Family History of learning disabilities, mental impairments, such as autism or other behavioral disorders, family history of female infertility, family history of adults with late onset (after 50) onset neurological difficulties, such as intention tremor, ataxia, memory, or cognitive decline.

Treatments and Interventions
for Fragile X Syndrome

X symbols for Fragile X syndrom

While a cure currently does not exist, FRAXA funded research has helped us to discover that the FMR protein helps shape the connections between neurons (brain cells) that trigger learning and memory.

Research is also starting to show how the lack of this protein causes Fragile X syndrome due to delaying the development of neurons, rather than damaging or destroying them. With this knowledge we now know that innovative treatments will benefit all individuals with Fragile X, regardless of age.

At this time treatments for autism and pervasive developmental disorders are frequently used. This may include occupational therapy for children (sensory integration), speech therapy, medications, academic and behavioral interventions, and possibly even applied behavior analysis.

They also appear to be working on some new medications that may help with symptoms. Clinical trials for these are in the process of being conducted to determine their effectiveness. Two of these are considered to be mGluR5 antagonists and one is considered to be a GABA(b) agonist.

For more information about Fragile X, you can visit The National Fragile X Syndrome Foundation.

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1. The National Fragile X Foundation. What is Fragile X? www.fragilex.org

2. FRAXA Research Foundation. Diagnoses and Treatment. www.fraxa.org. 7-2-12.

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