Hft | Learning Disabilities | Fragile X syndrome

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What is Fragile X syndrome?


Fragile X syndrome is known for being the most commonly inherited cause of learning disability. It affects boys more than girls, and boys are more likely to have a severe learning disability as a result, requiring more day to day support – though this is not true of all cases.

It is caused by the loss of a protein called the fragile X mental retardation protein (FMRP). People can act as carriers for the fragile X pre-mutation that can lead to fragile X syndrome, and develop some of the symptoms of the condition.

Some studies indicate that fragile X syndrome affects how people’s brains process sensory input. It is often difficult to detect during early years, as physical characteristics are not immediately obvious, and typical behaviours may not be immediately obvious.  If and when fragile X syndrome is suspected, genetic testing will confirm. Because fragile X can be inherited, testing for family members will be offered, as there will be implications for relatives.

While some people with fragile X syndrome will be able to live independently, others will need support to live the best life possible.

Signs of fragile X syndrome

Characteristics can vary, and affect people to differing degrees.  They typically include:

  • learning disability, usually more severe in boys. Not all girls will have an associated learning disability
  • short attention spans and impulsiveness
  • good memory skills
  • characteristic long face, and prominent jaw bones and ears
  • delayed speech/language skills
  • sensory issues
  • symptoms often associated with autism

Support for people with fragile X syndrome

  • Hft supports adults with learning disabilities including those with fragile X syndrome to live the best life possible. Contact your local service to discuss support options.
  • If you’re a family carer for someone with fragile X syndrome, Hft’s Family Carer Support Service can help with guidance and advice on support options and some of the benefits that are available.
  • The Fragile X Society provides more information and guidance for people with fragile X syndrome and their families.