Williams Syndrome Information

What is Williams Syndrome?

Williams Syndrome (or Williams-Beuren Syndrome) is a rare genetic disorder that is caused by the deletion of genetic material on chromosome 7. In more technical terms: Williams syndrome is the result of a deletion of the 7q11.23 region of chromosome #7 containing 26-28 genes, including the elastin gene. Elastin is the “marker gene” for Williams syndrome.

Williams Syndrome occurs in 1 in 7,500 to 1 in 20,000 births. The syndrome was first identified in 1961 by New Zealander J.C.P. Williams, but more is being understood and more information about Williams Syndrome is becoming available every year.

There are many symptoms that vary from person to person, however common there are some common medical problems, including cardiovascular disease, developmental delays, and learning challenges. That said, these medical problems often occur side by side with striking verbal abilities, highly social personalities, and an affinity for music.

There are different joys and challenges for each persona and family; some individuals are highly capable, living very independent lives; others need more assistance.

In Australia, we have access to some very useful early intervention and support services which can make a big difference to helping our WS members with their development, education and health.

Diagnosing Williams Syndrome

Diagnosis During Pregnancy

Diagnosing Williams Syndrome during pregnancy can be difficult to pick up. The only way a diagnosis can be made during pregnancy is with the follow blood tests.


A laboratory can use the technique known as fluorescent in situ hybridization (FISH) to confirm the diagnosis of Williams syndrome. FISH is a type of specialized chromosome analysis utilizing specially prepared elastin probes. If a patient has 2 copies of the elastin gene (one on each of their chromosomes #7), they probably do not have WS. If the individual only has one copy, the diagnosis of WS will be confirmed.

The laboratory will need 5 ml of blood drawn in a Sodium heparin tube. Results are usually available in 2-4 weeks.

The FISH test is readily available at major hospitals and cytogenetics laboratories around the country, but it is not a routine test. Therefore, not all labs will do FISH-based diagnosis. Families or their physicians should call the lab in advance to make sure they can perform the test.


A chromosomal microarray is a newer and preferred diagnostic tool that uses millions of markers to determine if there are missing pieces or extra pieces of DNA anywhere in the person’s chromosomes.  This test is slower but gives more information about the missing piece of genetic material. The size of the deletion as well as the genes contained in the deletion are very important factors as they can offer clues to the severity of characteristics in an individual.

Diagnosis After Pregnancy

Lack of intervention at a young age is a serious issue for children. Due to its rarity, Williams Syndrome it is often left undiagnosed for long periods of time, which can result in failure to obtain the correct support and treatment required.

Clinical diagnosis is not always easy as the signs can vary considerably but the different clues can be added up to produce a near-certain diagnosis. This diagnosis is generally confirmed through genetic testing. Developmental and physical signs can include (but are not limited to)-

Developmental/Early Problems

These can include low birth weight, slow weight gain (sometimes weight loss), below average growth, very slow feeding, restless sleeping and irritability, sometimes a hernia, a squint and excessive vomiting leading to dehydration and constipation. A raised calcium level is found in some babies.

Development delays will most likely occur for most infants with Williams Syndrome. Delays can include not meeting milestones such a smiling sitting, standing, crawling and walking.


Facial Features: All the children have a facial similarity, referred to as ‘elfin’ features. They include a wide mouth, with large, slack bottom lip; very retrousse nose with flattened bridge; slightly ‘bulgy’ cheeks; irregular teeth widely spaced; sometimes a squint.

Heart Problems: All Williams Syndrome individuals appear to have a slight narrowing of the aorta above the valve, in many cases insignificant but occasionally leading to more serious heart defects.


Hyperactivity in early years: extreme uninhibited behaviour, excessive talking, in an inappropriate and ‘adult’ manner, over-friendliness with strangers; compulsion to talk to adults, while being unable to make friends with peers. High verbal ability leading to artificial expectations of matching mental ability. Obsessional interest in certain things: e.g. cars, trains, hoovers, wheels, etc. Fear of heights, open stairs, uneven surfaces. Very short concentration span adding to learning difficulties, high distractibility. Emotional immaturity exhibited by over-reaction to events, and exaggerated displays of fear, excitement, sadness, happiness etc.                         

Hypersensitivity to Noise: This is the clue most common to all Williams Syndrome children: about 90% show great distress on hearing sudden loud noises, such as guns firing, balloons bursting, Christmas crackers, fireworks, etc.

After Diagnosis

Learning that your child has a syndrome can be overwhelming. Accepting the news emotionally, dealing with immediate medical concerns, and preparing for ongoing development issues can make every day go by in a blur for days, weeks or even months. Often, just knowing where to start can be helpful.

Please refer to our private Facebook Group to not only find out more information about Williams Syndrome, but also to seek support from parents that have been in your position you’re in and experienced the feeling and emotions your having (which are all completely normal).

At this stage, there is no ‘cure’ for Williams Syndrome as it is caused by a genetic chromosomal defect.

Once you’ve worked through this extremely emotional period, its time to work towards placing supports in place to best support your child. If your eligible to receive NDIS funding, see our NDIS support page for more information. Your support team may include (but not limited to):

Specialist Doctors: Paediatrician, Cardiologist, Gastroenterologist, Endocrinologist, Urologist Optometrist, Psychologist, Psychiatrist and Dentists.

Allied Health Professionals: Physiotherapist, Occupational Therapist, Speech Therapist.