What Causes Williams Syndrome?

What Causes Williams Syndrome?

Williams syndrome is a rare neurodevelopmental condition that affects the cognitive development and facial structure of individuals who have it. Williams syndrome is rare, affecting only 1 in every 10,000 children born in the United States. Individuals with Williams syndrome often have unique personality characteristics, such as over-friendliness and high levels of empathy and anxiety. Many people are unaware of Williams syndrome due to its rarity, and some individuals will go their entire lives without being diagnosed with it. The Special Olympics Arizona team is breaking down this rare genetic mutation: what causes it, the risk factors, and other questions parents might have about Williams syndrome.

What Causes Williams Syndrome?

Williams syndrome is caused by a partial deletion, or missing piece, of up to 28 genes on chromosome 7. Our bodies have 46 chromosomes in total, arranged into 23 pairs. Within each chromosome is a segment of DNA known as a gene, all of which play a unique role in telling our body how to form and function. This missing section of genes on chromosome 7 will cause the signs and symptoms of Williams syndrome. Some of the genes that will be missing on chromosome 7 are thought to play a part in the production of elastin in the body. Elastin is a protein that provides elasticity and suppleness to various structures in the body, including the blood vessel walls and skin. The lack of elastin due to the missing genes that produce elastin causes some of the physical characteristics that are recognizable in individuals with Williams syndrome.

The majority of Williams syndrome cases are the result of unintentional genetic mutations that take place during the development of the egg or sperm in an unaffected person. In some cases, very rarely, William syndrome can be inherited from a parent who has the condition. When it is inherited, it will be inherited in an autosomal dominant manner, meaning that just one copy of the genetically altered chromosome 7 is enough to cause symptoms of the condition. The autosomal dominant inheritance method means that an individual with Williams has a 50% chance of passing on the syndrome to any future children.

How Common is Williams Syndrome?

Williams syndrome is rare, occurring in only about 1 in every 10,000 births.

Is Williams Syndrome Inherited?

Williams syndrome is primarily a result of spontaneous genetic mutations that occur during the development of the sperm or the egg and is not an inherited condition. These cases occur in individuals who have no family history of Williams syndrome. If a parent is unaffected by Williams syndrome but has a chromosomal change, called an inversion, in the region of chromosome 7 associated with Williams syndrome, they may be at an increased risk of having a child with Williams syndrome.

Very rarely, Williams syndrome can be inherited from a parent who has it. It is known as an autosomal dominant condition, which means that just one copy of the altered chromosome 7 present in each cell is sufficient to cause the disorder and all associated symptoms.

Can Williams Syndrome Be Prevented?

Since Williams syndrome is a spontaneous genetic mutation, there is no way to prevent it from occurring. If you or a family member has been diagnosed with Williams syndrome, it can be helpful to speak with a genetic counselor to discuss the potential possibility of passing Williams syndrome along to a child. While there is no way to prevent Williams syndrome, working with a genetic counselor can provide you with guidance and knowledge to make decisions as to how to move forward with it.

How is Williams Syndrome Diagnosed?

Williams syndrome is generally diagnosed when a child is a baby or in early childhood. When a doctor suspects that a child may have Williams syndrome, they will typically perform a physical examination on the child before performing genetic testing, which involves a blood test to identify differences in genes. Additional tests that could be conducted to confirm Williams syndrome include an EKG or echocardiogram, which is an ultrasound of the heart used to check for irregularities; a blood pressure test; and a sample of urine to test the kidneys for any irregularities.

Is There a Cure for Williams Syndrome?

There is currently no cure for Williams syndrome, but advances in treatments for the condition have helped make the lives of individuals living with it much easier. There are many condition management options for individuals with Williams, as well as treatments and interventions to help manage the symptoms and side effects of the disorder. Interventions and treatments include:

• A formal cardiologist evaluation, which will be used to determine if there is an issue with your child’s heart and what course of action will be taken.
• Enrolling in early intervention programs including therapies and special education programs to help alleviate any developmental delays and learning disabilities.
• Visiting a nutritionist or a nephrologist to treat blood calcium levels.
• Working with other specialists to determine how and when to treat symptoms as needed.

While Williams syndrome is rare, developing connections with other parents of children with Williams syndrome can provide you with guidance and support, as well as help build a community of peers your child can relate to. This may help emotionally and developmentally when moving forward with the Williams diagnosis.