Williams Syndrome

What is Williams syndrome?

Williams syndrome, also known as Williams-Beuren syndrome, is a rare, neurodevelopmental, genetic condition characterized by many symptoms including unique physical features, delayed development, cognitive challenges and cardiovascular abnormalities. Williams syndrome may cause poor growth in childhood, and most adults with the condition are shorter than average. Williams syndrome can also cause endocrine concerns like having too much calcium in your blood and urine, an underactive thyroid and early puberty.

Who does Williams syndrome affect?

Williams syndrome usually occurs when someone is missing a small piece of chromosome 7. This means that most people with Williams syndrome have not inherited the condition from a parent. People with Williams syndrome have a 50% chance of passing the condition on to their children.

How common is Williams syndrome?

Williams syndrome is a rare condition that occurs in an estimated 1 in every 10,000 births in the United States.

How does Williams syndrome affect my child?

As your child grows, they may face challenges as a result of their diagnosis, but they can reach their full potential with early intervention and treatment. Children may have birth defects involving their heart or blood vessels around it that sometimes need surgery to correct. They will need routine blood and urine tests to keep their kidneys healthy. They often sit and walk a bit later than other children due to loose joints. Often, children with Williams syndrome have strong verbal and communication skills, which could mask delays to their cognitive abilities, which are common in Williams syndrome-like learning numbers and letters, differentiating between real and abstract and their ability to understand the space between objects. Most children with Williams syndrome have an excellent long-term memory but may experience attention-deficit/hyperactivity disorder (ADHD).

What causes Williams syndrome?

A deletion, or missing piece, of a region on chromosome 7 causes Williams syndrome.

In our bodies, we have 46 chromosomes total, arranged into 23 pairs. We inherit one copy of a chromosome in each pair from our parents. Within our chromosomes are segments of DNA (genetic information) known as genes. Our genes are our body’s instruction manual that tells it how to form and function.

People with Williams syndrome are missing a portion of chromosome 7, which is made up of several genes. Since your genes are an instruction manual to your body, if you're missing chromosomes, your instruction manual is missing a few pages that describe how chromosome 7 should function. The missing pages in your instruction manual cause symptoms of Williams syndrome.

What are the symptoms of Williams syndrome?

Williams syndrome may cause symptoms that range in severity. Not all people with Williams syndrome will have the same set of symptoms.

Symptoms of Williams syndrome include:

• Chronic ear infections and/or hearing loss.
• Dental abnormalities, such as poor enamel and small or missing teeth.
• Elevated calcium level in the blood.
• Endocrine abnormalities: hypothyroidism, early puberty and diabetes in adulthood.
• Farsightedness.
• Feeding difficulties in infancy.
• Scoliosis (curve of the spine).
• Sleep problems.
• Unsteady walk (gait).

Many of the symptoms of Williams syndrome occur in other conditions that are not Williams syndrome and could lead to multiple diagnoses.

Developmental delays

Symptoms of Williams syndrome can cause delays for children to reach developmental milestones, which are things that your child can do by a certain age. Developmental milestones showcase how your child thinks, learns, speaks, plays, moves and behaves. Williams syndrome can delay milestones including:

• Learning (mild to moderate intellectual challenges).
• Saying their first words and talking.
• Sitting and walking from a low body tone (hypotonia).
• Socializing (outgoing and very friendly, difficulty identifying strangers, attention problems, excessive empathy, phobias or anxiety).

Serious symptoms of Williams syndrome

One of the more serious symptoms of Williams syndrome is cardiovascular disease. The narrowing of various blood vessels near the heart is common during fetal development (stenosis), which can lead to increased blood pressure, arrhythmia (irregular heartbeat) and ultimately cardiac failure. Cardiac involvement is often one of the first signs that your child may have Williams syndrome.

Physical characteristics of Williams syndrome

A symptom of Williams syndrome is unique physical characteristics that are present when your child is born including:

• Full cheeks.
• Large ears.
• Prominent lips.
• Short stature.
• Small jaw.
• Upturned nose.
• Vertical skin folds that cover the inner corner of the eyes (epicanthal folds).
• Wide mouth.

How is Williams syndrome diagnosed?

The condition is typically diagnosed when your child is a baby or early during childhood. If your healthcare provider suspects your child has Williams syndrome, they will provide a physical examination of your child, followed by a genetic test, which is a blood test that identifies gene differences.

Often, your healthcare provider may ask for additional tests to confirm the diagnosis and check the symptoms of the condition. Other tests include:

• An EKG or echocardiogram (ultrasound of the heart) to check the heart for irregularities.
• Check your child's blood pressure for abnormalities.
• Test a sample of your child’s blood or urine to identify symptoms in your child’s kidneys.

How is Williams syndrome treated?

If someone has Williams syndrome based on physical findings and/or a positive genetic test result, your healthcare provider will work with appropriate specialists to help explain the diagnosis to the individual and their family, especially a genetic counselor.

Your provider will discuss condition management recommendations based on the diagnosis. Although there is no cure for Williams syndrome, it is important to identify and treat the side effects that can occur with this condition. Treatments and interventions must be based on the unique needs of each individual including:

• Obtaining a formal evaluation by a cardiologist. If a problem is found in your child’s heart, the cardiologist will determine the best treatment.
• Enrolling in early intervention programs, therapies or special education to alleviate developmental delays and/or learning problems.
• Visiting a nutritionist or a nephrologist to treat elevated blood calcium levels.
• Visiting specialists as needed to address any additional symptoms.

How can I reduce my risk of having a child with Williams syndrome?

Since Williams syndrome is a genetic condition caused by a chromosome change, not inherited from a parent, there is typically no way to prevent it. If you are planning on becoming pregnant and want to understand the risks of having a child with a genetic condition, talk with your healthcare provider about genetic testing.

What can I expect if I have a child with Williams syndrome?

Williams syndrome cannot be cured, but treatment is available to manage symptoms. It's important to seek a medical evaluation by your healthcare provider to receive a diagnosis, followed by visits to a specialist as needed to address any symptoms or side effects. Most people with Williams syndrome have a normal life expectancy, but some may have a reduced life expectancy due to complications of the disease (such as cardiovascular problems). Oftentimes, people with Williams syndrome will need additional support as they grow into adults.

How do I take care of my child with Williams syndrome?

If your child receives a Williams syndrome diagnosis, it's best to offer them as much love and support as you can. They will likely need to schedule regular visits with their healthcare provider and specialists to treat any symptoms of the condition that may arise, especially cardiovascular side effects. Your child might need to enroll in a special education program to address any challenges they might face in the classroom. Be patient with your child as they grow and adapt to the world around them at their own pace.

When should I see my healthcare provider?

You should visit your child’s healthcare provider if they:

• Miss developmental milestones.
• Get ear infections often or show signs of hearing loss.
• Have trouble eating.

When should I visit the ER?

If you notice your child shows signs of heart (cardiovascular) disease, visit the emergency room immediately. Symptoms of cardiovascular disease include:

• Blue or purple tone to the skin or lips.
• Breathing quickly.
• Difficulty eating.
• Fast heartbeat.
• Swelling throughout their body.

What questions should I ask my doctor?

• Does my child need to see a specialist to address any symptoms of Williams syndrome?
• If I plan on becoming pregnant, will future children receive the same genetic condition?
• Does my child need any medication to alleviate their symptoms?

A note from Cleveland Clinic

Although Williams syndrome is not contagious, your child’s friendly, outgoing personality is infectious. Always provide support to your child, because a new diagnosis can be overwhelming. Some people find that it helps to discuss their questions or concerns with experts, other individuals with Williams syndrome or parents who have children with Williams syndrome.