Signs & Symptoms of Fragile X Syndrome

Fragile X syndrome is a common type of intellectual disability that affects around 1 in 7,000 boys born worldwide and 1 in 11,000 girls born worldwide. Fragile X affects cognitive function and causes learning deficits in individuals, which can cause difficulties at home and at school for children. In addition to affecting cognitive function, fragile X often results in physical symptoms that many individuals with the condition will display. The Special Olympics Arizona team is breaking down these signs and symptoms that are commonly recognized in individuals with fragile X.

What Are the Symptoms of Fragile X Syndrome?

Fragile X syndrome, commonly referred to as FXS, is a genetic disorder that is caused by a mutation in the Fragile X Messenger Ribonucleoprotein, or FMR1, gene. The gene FMR1 is supposed to create a protein called FMRP that aids in the development of a babyâ€™s brain. When this FMR protein is not created at an adequate rate, it will result in intellectual disability or fragile X disorder. Individuals with this genetic mutation, fragile X, will often display intellectual, physical, and behavioral symptoms of the intellectual disability, although some signs will be more recognizable when an individual is younger and others will become more prominent as they age.

Intellectual Signs

Many individuals with fragile X will have intellectual difficulties and issues with cognitive functioning. These difficulties and delays can range in severity, and some individuals with fragile X will only have mild intellectual difficulties, while others may have more severe intellectual deficits. Among individuals with more mild intellectual difficulties, you may notice they have learning delays or difficulties with certain subjects, such as issues with understanding and solving math problems. Among individuals with more severe intellectual deficits, you may notice a learning disability or developmental disability that causes issues with speech and communication. Some common intellectual signs include:

Learning difficulties or learning disabilities.
A low intelligence quotient: Individuals with Fragile X will often have IQ scores that decrease with their age.
Delayed developmental milestones: Individuals with Fragile X will often have milestones that are delayed when compared to their peers. These delayed milestones include delayed speech and communication, delayed social milestones, and delayed learning, thinking, and problem-solving milestones.
Delayed non-verbal communication: Individuals with Fragile X will often have a delay in their development and understanding of non-verbal communication, such as gestures, body language, and facial expressions.
Language Processing: Individuals with Fragile X may begin showing signs that they have difficulty with language processing around the age of 2.

Physical Signs

Individuals with fragile X are not often born with recognizable physical symptoms of the intellectual disability, but as a child ages and goes through puberty, they may develop physical symptoms. Some of the physical symptoms you may begin to notice in individuals with fragile X include:

A long, narrow face.
A larger than average forehead.
A larger than average jaw.
Very soft skin.
Larger than average ears.
Eyes which are commonly crossed or lazy eyes.
Very flexible or double-jointed fingers.
Flat feet.
Enlarged testicles.
A high, arched palate.
Low muscle tone.

Behavioral Symptoms

Individuals with fragile X may have behavioral symptoms that are noticed at a young age. Many behavioral symptoms in individuals with fragile X syndrome are the result of communication difficulties and an inability to appropriately express themselves. Common behavioral symptoms among individuals with fragile X include:

Attention deficit/hyperactivity disorder, more commonly known as ADHD.
Social anxiety and extreme shyness.
Flapping or biting their hands, especially in situations of stress.
Poor eye contact; difficulty maintaining or initiating eye contact.
Sensory disorders, such as difficulty being in a crowd, sensitivities to certain fabrics or feelings, or sensitivity or aversion to certain smells, tastes, or sounds.
Difficulty picking up on social cues.
Aggressiveness or irritability.
Self-injury behaviors.

Speech and Language Problems

Individuals with fragile X syndrome will often have speech and language problems. They often have trouble speaking or may stutter when trying to speak or leave out parts of words, making it difficult to understand what they are trying to say. They may also have difficulties with some of the intricacies of language, such as understanding tone of voice, body language, or other social cues. Children with fragile X syndrome may begin talking later in life than their peers, although the majority of children with fragile X syndrome do begin talking eventually, though they may experience difficulties. A small number of individuals with fragile X will remain non-verbal throughout their lives.

Sensory Issues

Many children with fragile X syndrome will have sensory issues, such as difficulty handling certain sensations and feelings. They may be bothered by things such as bright lights, certain fabrics on their clothing, or loud noises. Communication difficulties may make it difficult for children to express their sensory discomfort, sometimes leading them to act out.

Associated Conditions and Disorders

In some cases, individuals with fragile X syndrome will be at greater risk of developing associated conditions or disorders. Some of these associated conditions include:

Seizures: Individuals with fragile X syndrome may be at greater risk of having or developing epilepsy, which is a disorder of the brain that is characterized by frequent seizure episodes.
Sleep problems: Many individuals with fragile X syndrome will have sleeping problems. According to studies, around 4 in 10 individuals with fragile X syndrome will have difficulties sleeping, such as insomnia.
Obesity: Individuals with fragile X syndrome are at a greater risk of developing obesity than individuals without fragile X syndrome.
Self-injury behaviors: Individuals with fragile X syndrome may be prone to self-harming behaviors in difficult and stressful situations.
Aggressiveness: Individuals with fragile X in addition to autism spectrum disorder are more likely to be aggressive and irritable than individuals without fragile X in addition to autism spectrum disorder.