Introduction

22q11 Deletion Syndrome is one of many genetic disorders treated by the Cardiovascular Genetics team. A good place to start learning about how 22q11 deletion syndrome fits into cardiovascular genetics is by browsing the CVG Frequently Asked Questions categories:

Answers to the following questions can be found in the categories listed above: What is cardiovascular genetics? What is congenital heart disease? Why congenital heart disease happens? How is congenital heart disease inherited? Do all genetic changes have an impact on our health? Are all genetic changes inherited? What is genetic testing? What are the Cardiovascular Genetic Services available?

Last Update 2-1-05

Nomenclature: What's in a Name?

If you have been told that your child has a Chromosome 22q11 Deletion, the doctor may have used a number of different terms to describe the diagnosis. It may have been called 22q11 Deletion Syndrome, Velocardiofacial Syndrome, Shprintzen Syndrome, Di George Syndrome, CATCH-22, 22q minus, Conotruncal Anomalies Face Syndrome, or Sedlackova Syndrome. The benefit of using 22q deletion syndrome is that is describes the change in the genetic information and does not refer to any specific medical symptoms. For more information, please read The Name Game.

Last Update 06-14-06

Genetics

Most people have two Chromosome 22s in each of the cells of their body. 22q11 Deletion Syndrome refers to the loss of a small amount genetic information on one of those two Chromosome 22s. This loss is called a deletion. In the case of 22q11 deletion syndrome, the deletion occurs in a region of genetic material that has important instructions (genes) to the body on how to develop, grow and repair itself.

Everyone has changes in their genetic information. Sometimes our bodies have ways (mechanisms) to detect, identify, and repair these changes. Sometimes, these changes persist. If a change endures, depending on when in our development and where in our bodies it occurs, it can have an impact on our health. The impact may be unnoticeable, minor, or severe. When changes occur early in development and are not automatically corrected by our bodies, those changes will be found in all or most of our cells. For people with a 22q11 deletion, this deletion occurred early in embryonic development and will be found in all (or most) of that person’s cells.

When a genetic change (mutation) occurs for the first time in an individual, it is known as sporadic. Most often, a child with 22q11 Deletion Syndrome is born in the absence of a family history. While 22q11 Deletion Syndrome is usually sporadic, it can also be inherited. Since 22q11 deletions can be inherited, parents are routinely offered the option to undergo deletion testing (also known as FISH 22q) as well. These family studies are performed to determine whether any other family member is at risk for unidentified 22q11 deletions. In other words, while the deletion has been associated with a broad spectrum of health concerns, there are possibly individuals who have the deletion and no easily recognizable manifestations. If neither parent has the deletion, then the affected child’s case would be considered sporadic.

For someone who has a 22q11 deletion, there is a one in two (50%) chance for any given pregnancy of passing the deletion to a child. This pattern of inheritance is called autosomal dominant.

Last Update 06-18-04

Findings

Most people with a 22q11 deletion have some medical concerns. The most common medical problems include congenital heart disease, palatal abnormalities, parathyroid function problems, immune deficiency, and learning disabilities.

It is important to note that some people have no clinical findings, some have one or a few findings, and some have numerous issues that require medical attention. There is a long list of medical concerns that have been associated with 22q11 deletions. A person with a 22q11 deletion might be at higher risk to be born with or to eventually develop one or some of these problems. Of course, no one has all the findings and most affected individuals have only a few medical issues. Some findings only become problems at particular stages of development or at different ages. Knowing about the deletion however, alerts parents to potential areas of concern. Having an awareness of these potential concerns can help parents to detect problems as they arise, and to seek treatment and/or assistance if necessary.

Velocardiofacial Syndrome (VCFS) is one of the more familiar names given to the 22q11 Deletion Syndrome. VCFS is a term that describes some of the areas that are most commonly involved in the condition. The term is derived from the Latin words “velum”, that means palate, “cardia”, which means heart, and “facies” which refers to the face.

Palate problems can include velopharyngeal incompetence, bifid uvula, and/or soft palate cleft. These abnormalities sometimes cause children with 22q Deletion Syndrome to have feeding and/or speech difficulties.

It is important to remember that almost half of those with 22q11 deletions have no obvious heart defect. Characteristic cardiac problems include Interrupted aortic arch, Truncus Arteriosus, Tetralogy of Fallot, and Pulmonary Atresia. Simpler forms of heart disease (e.g., VSD, ASD, Right Aortic Arch, vascular changes) also occur.

Other commonly associated problems involve the parathyroid gland and/or immune system. Changes in the structure or functioning of the parathyroid gland may lead to low calcium levels (hypocalcemia). Calcium is an important component for maintaining a healthy body. Calcium helps bones get stronger and permits proper functioning of the nervous system, heartbeat, and metabolic system. Although immune abnormalities may be present, it is unusual for these to lead to noticeable immune deficiency. While ear infections do tend to be common, this is more likely attributed to structural problems in the soft palate. Some patients may have characteristic facial features; frequently, these are usually subtle and change with age.

Most children who are diagnosed with 22q Deletion Syndrome will have a through medical examination to rule out any specific health problems such as heart disease, kidney problems, recurrent infections, palate abnormalities, or low calcium levels. Depending on the age of the patient with 22q Deletion Syndrome, it is expected that certain clinical findings will be present. Therefore, the needs of a child with this condition may change according to the age and the existing health problems (Genet Couns 1999;10(1):79-88).

Last Update 09-10-04