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Fragile X syndrome

Fragile X syndrome and learning disability explained, and where to find the right support.

What is Fragile X syndrome?

Fragile X is a genetic condition that affects both boys and girls, although boys are often more severely affected.

It can cause a range of issues with language, emotions, attention, behaviour and social interaction.

Fragile X and learning disability

Fragile X is the most common inherited cause of learning disability.

Of the people who have Fragile X, nearly all boys will have a learning disability but only a third of girls. The learning disability could be mild, moderate or severe, which will affect the amount of support the person needs day-to-day. 

A child smiling next to an abacus

How does Fragile X affect someone?

Someone with Fragile X might have a short attention span, be easily distracted, act impulsively, feel restless, be very active, and have heightened senses, but no two people are the same.

Many people with Fragile X might act in a way that is similar to someone with autism , including avoiding eye contact, feeling anxious in social situations, extreme shyness, enjoying familiar routines and hand flapping or hand biting.

People with Fragile X share some physical features, including a long narrow face with prominent jaw bones and ears. These features are difficult to see in young children, which is why diagnosis can sometimes be delayed.

How is Fragile X diagnosed?

Fragile X can be diagnosed with a blood test. It cannot be diagnosed through physical features or behaviour.

Because it is a genetic condition, it is possible to test individuals to find out if they are a ‘carrier’ of the gene, and could pass it on to their children. Diagnosis before the child is born is also possible.

Two people smiling and looking at each other.

Living with Fragile X

Most people with Fragile X will need support with their speech and language, and with social and emotional interaction with others.

Some people with Fragile X also develop epilepsy, and a few have autism. This may also have an impact on the kind of support they need, both as a child and as an adult.

With the right support, it is possible for someone with Fragile X to lead a fulfilling life, in the way they choose.

For more information about Fragile X visit:

Information about Fragile X

Fragile X is the most common inherited cause of learning disability.

Of the people who have Fragile X, nearly all boys will have a learning disability but only a third of girls. The learning disability could be mild, moderate or severe, which will affect the amount of support the person needs day-to-day.

Fragile X is a genetic condition that affects both boys and girls, although boys are often more severely affected.

It can cause a range of issues with language, emotions, attention, behaviour and social interaction.

Someone with Fragile X might have a short attention span, be easily distracted, act impulsively, feel restless, be very active, and have heightened senses, but no two people are the same.

Many people with Fragile X might act in a way that is similar to someone with autism, including avoiding eye contact, feeling anxious in social situations, extreme shyness, enjoying familiar routines and hand flapping or hand biting.

People with Fragile X share some physical features, including a long narrow face with prominent jaw bones and ears. These features are difficult to see in young children, which is why diagnosis can sometimes be delayed.

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