22q11 deletion syndrome (22q11DS)

What is 22q11 deletion syndrome?

22q11 deletion syndrome (22q11DS) is a genetic condition that affects about 1 in 2000 to 1 in 4000 children. 22q11DS is known by several other names including velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome. 22q11DS is the second most common genetic condition after Down syndrome.

People with VCFS, DiGeorge syndrome and 22q11DS all have the same genetic cause: a small missing piece of genetic material (DNA) on one of their two copies of chromosome 22. This missing genetic material is called a deletion.

22q11 deletion

In most cases, 22q11DS is the result of a new genetic change that occurs when a baby is conceived. This is called a de novo deletion and occurs by chance in either the mom’s egg or the dad’s sperm. A de novo deletion is not caused by anything the parents did before or during the pregnancy.

In some people with 22q11DS (about 10%), the deletion is inherited from a parent. Sometimes a parent might not know that they have 22q11DS until after they have a child diagnosed with this condition.

Symptoms of 22q11DS

A syndrome is a group of signs and symptoms that occur together due to a common underlying cause. 22q11DS can affect many parts of the body​ and each person with 22q11DS can be affected in a different way. Some of the common features of 22q11DS include:

• heart defects
• palate differences
• immune deficiency
• feeding and swallowing problems
• low levels of calcium in the blood
• growth delay
• kidneys that are smaller, or formed differently
• speech and language impairments
• learning disabilities
• psychiatric disorders (anxiety, attention deficit, depression, psychosis)

Some individuals will experience many of the symptoms while others may experience only a few. Every person is different.

How 22q11DS is diagnosed

22q11DS is diagnosed by a blood test. Three different genetic tests can detect 22q11DS:

• Fluorescent In Situ Hybridization (FISH) is a test that looks specifically for a deletion on chromosome 22. This test can miss small or atypical 22q11 deletions.
• Chromosome microarray is a test that looks for extra or missing pieces across all the chromosomes. This test can detect small or atypical 22q11 deletions.
• MLPA is a DNA test that looks for missing or extra pieces in chromosome region 22q11. This test can detect small or atypical 22q11 deletions.

Only one of these tests is typically needed to make a diagnosis of 22q11DS. The test that is ordered by your child's doctor is chosen based on your child’s presentation.

It usually takes several weeks to get these test results back depending on the test chosen and the laboratory. Ask your health-care provider about your specific situation.

Treatment of 22q11DS

Although there is no cure for 22q11DS, symptoms can be treated and managed. People with 22q11DS may need continued support in some aspects of their life throughout adulthood. With this support, people with 22q11DS can lead happy, productive lives.