Williams syndrome (WS) is a genetic condition that is present at birth and can affect anyone.  It is characterized by medical problems, including cardiovascular disease, developmental delays, and learning disabilities.  The most significant medical problem associated with WS is the cardiovascular disease caused by the narrowed arteries. WS is also associated with elevated blood calcium levels in infancy. A random genetic mutation (deletion of a small piece of chromosome 7), rather than inheritance, most often causes the disorder. Williams syndrome is considered an autosomal dominant condition because one copy of the altered chromosome 7 in each cell is sufficient to cause the disorder. In a small percentage of cases, people with Williams syndrome inherit the chromosomal deletion from a parent with the condition.

Most cases of Williams syndrome are not inherited but occur as random events during the formation of reproductive cells (eggs or sperm) in a parent of an affected individual. These cases occur in people with no history of the disorder in their family.

However, individuals who have WS have a 50 percent chance of passing it on if they decide to have children. These often occur side by side with striking verbal abilities, highly social personalities and an affinity for music.

WS affects 1 in 7,500 – 10,000 people worldwide – an estimated 20,000 to 30,000 people in the United States. It is known to occur equally in both males and females and in every culture.

Unlike disorders that can make connecting with your child difficult, children with Williams syndrome tend to be social, friendly and endearing.  Parents often say the joy and perspective a child with WS brings into their lives had been unimaginable.

But there are major struggles as well.  Many babies have life-threatening cardiovascular problems.  Children with WS need costly and ongoing medical care and early interventions (such as speech or occupational therapy) that may not be covered by insurance or state funding.  As they grow, they struggle with things like spatial relations, numbers, and abstract reasoning, which can make daily tasks a challenge. As adults, most people with Williams syndrome will need supportive housing to live to their fullest potential.  Many adults with WS contribute to their communities as volunteers or paid employees; often working at assisted living homes for senior citizens, hospitals and libraries, or as store greeters or veterinary aides.

 However, individuals who have WS have a 50 percent chance of passing it on if they decide to have children. The characteristic facial features of WS include puffiness around the eyes, a short nose with a broad nasal tip, wide mouth, full cheeks, full lips, and a small chin. People with WS are also likely to have a long neck, sloping shoulders, short stature, limited mobility in their joints, and curvature of the spine. Some individuals with WS have a star-like pattern in the iris of their eyes. Infants with WS are often irritable and colicky, with feeding problems that keep them from gaining weight. Chronic abdominal pain is common in adolescents and adults. By age 30, the majority of individuals with WS have diabetes or pre-diabetes and mild to moderate sensorineural hearing loss (a form of deafness due to disturbed function of the auditory nerve). For some people, hearing loss may begin as early as late childhood. WS also is associated with a characteristic “cognitive profile” of mental strengths and weaknesses composed of strengths in verbal short-term memory and language, combined with severe weakness in visuospatial construction (the skills used to copy patterns, draw, or write). Most older children and adults with WS speak fluently and use good grammar. More than 50% of children with WS have attention deficit disorders (ADD or ADHD), and about 50% have specific phobias, such as a fear of loud noises. The majority of individuals with WS worry excessively.

Unfortunately there is no cure for Williams syndrome, nor is there a standard course of treatment. 

The prognosis for individuals with WS varies. Some degree of impaired intellect is found in most people with the disorder. Some adults are able to function independently, complete academic or vocational school, and live in supervised homes or on their own; most live with a caregiver.

Where you can find additional information about Williams syndrome:

You may find the following resources about Williams syndrome helpful. These materials are written for the general public.

• MedlinePlus – Health information (4 links)

• Genetic and Rare Diseases Information Center – Information about genetic conditions and rare diseases (2 links)

• Additional NIH Resources – National Institutes of Health (2 links)

• Educational resources – Information pages (7 links) and Patient support – For patients and families