What is Fragile X syndrome?
People with Fragile X syndrome (or Fragile X) have intellectual disability, behavioural and learning challenges as well as certain physical characteristics. Fragile X is the most common cause of inherited intellectual disability, and also the most common genetic cause of autism.
Fragile X is caused by a change in a single gene, the FMR-1 gene. This gene helps create a protein that is needed for healthy brain development.
Types of Fragile X syndrome
Depending on how a person’s FMR1 gene has been changed by the Fragile X mutation, they are said to either have the full mutation, or a pre-mutation.
People with the full mutation show symptoms of Fragile X. People with the pre-mutation may not show any symptoms, but are carriers of Fragile X.
Symptoms or signs of Fragile X syndrome
Fragile X can affect people differently, and can cause many different types of problems such as:
- intellectual disability, slow development and difficulties with communication, coordination, motor skills and learning
- behavioural problems such as aggression, anxiety, shyness and repetitive speech
- physical symptoms such as weak muscles and joints, a heart murmur and a high palate.
Fragile X syndrome diagnosis
A diagnosis of Fragile X can be made at any age, by doing a blood test. This test can show whether or not you are affected by Fragile X, and whether or not you are a genetic carrier.
If you or your partner have Fragile X or are a carrier, and are expecting a baby, you might be able to get a pre-natal test to find out whether your baby will be affected.
Visit Pregnancy, Birth and Baby website for more information about Fragile X and babies.
Carriers of Fragile X
Carriers of Fragile X might develop certain health conditions later in life, such as:
- Fragile X tremor ataxia syndrome, or FXTAS, which causes a tremor and mainly affects men over 50 years
- Fragile X primary ovarian insufficiency, or FXPOI, which can cause infertility and early menopause in women.
Living with Fragile X syndrome
Although there is no cure for Fragile X, treatments (including some medications) can help improve quality of life, especially if received early on. Ideally, each person with Fragile X will be cared for by a multidisciplinary team of health professionals.
Where to go for help
The Fragile X Association of Australia provides support to families living with Fragile X syndrome. This includes specialised clinics, workshops, counselling and casework.
Visit healthdirect's genetic disorders guide to learn more about genes, types of genetic disorders and where to go for help and more information.
Last reviewed: July 2016