Williams Syndrome

What is Williams syndrome?

Williams syndrome is a rare genetic condition that occurs in about 1 in every 20,000 people. It happens spontaneously, which means it is not passed down from one generation to the next. The children who have it are missing genetic material on chromosome 7. This chromosome includes the gene that makes a protein that ensures the walls of blood vessels are flexible.

Children with Williams syndrome have physical and developmental problems, are very outgoing, and have poor motor control. While they are competent in certain areas, they tend to be moderately to mildly developmentally delayed.

Physically, they tend to be short, have small upturned noses, a long upper lip, wide mouth, small chin, and puffiness around the eyes. This is sometimes described as an "elfin" appearance. These children may also have dental and kidney abnormalities, sensitive hearing, and musculoskeletal problems.

What heart conditions are associated with Williams syndrome?

Most children with Williams syndrome have a heart or blood vessel problem. Narrowing of the aorta is common, producing supravalvular aortic stenosis, or SVAS, as is narrowing of the pulmonary arteries. The degree of severity varies.

What is the outlook for children with Williams syndrome?

The outlook for these children varies. Some with Williams syndrome go on to lead full lives, becoming self-sufficient, completing school, and working.

For more information about Williams syndrome, please ask to be referred to a genetic counsellor.

Fraser Golding, MD, FRCPC