Fragile X Syndrome: Symptoms, Cause, Diagnosis and Treatment

Fragile X syndrome (FXS) is a condition that children are born with. Children with FXS may have speech and language delays, as well as learning and behavior challenges.

FXS is a common inherited cause of intellectual disability (challenges with learning and daily life skills) and a known cause of autism.

Boys affected by FXS may be taller than average as they grow older. They may also have a larger head, longer face, larger ears or enlarged testicles. Not all boys with FXS have these features. Girls with FXS are less likely to have noticeable physical features.

Cause

Fragile X syndrome is caused by changes in the FMR1 gene.

Diagnosis

Doctors use a genetic test to check for fragile X syndrome. It looks for changes in the FMR1 gene. A large change confirms the child has FXS. A smaller change does not mean the child has FXS, but it can be passed on to future children and may increase the risk of some health problems.

Children showing signs of autism, speech and language difficulties or trouble moving from one activity to another should be tested for FXS.

Treatment

There is no cure for FXS. However, treatment and support can help children reach their full potential. New precision treatments for fragile X syndrome are actively being studied. Care is based on each child’s needs and may help with learning, communication and behavior.