22q11.2 Deletion Syndrome (DiGeorge Syndrome)

What is 22q11.2 deletion syndrome?

22q11.2 deletion syndrome is a genetic condition that causes a combination of medical problems. These problems can vary widely from child to child, but may include heart defects, cleft palate, speech or feeding problems, difficulty fighting infections, low calcium levels, kidney problems, learning or behavioral issues, and facial differences. Different names may be used for various combinations of symptoms, including DiGeorge, velocardiofacial or Shprintzen, conotruncal anomaly face, Opitz G/BBB, and Cayler cardiofacial syndromes. To avoid confusion, health care providers now typically call all of these conditions 22q11.2 deletion syndrome, because they have the same underlying genetic cause despite their varying symptoms.

What is the cause of 22q11.2 deletion syndrome?

This condition is caused by a missing a part of chromosome 22. The specific area of the chromosome that is missing is 22q11.2. The exact size and location of the missing chromosome can vary and this is thought to explain some of the variability in medical problems associated with the disorder. About 10 to 15 percent of cases are inherited. A parent with 22q11.2 deletion has a 50 percent chance of passing it on to each of their children. It’s estimated that about 1 in 4,000 children are born with 22q11.2 deletion syndrome, however it may actually be more common since mild cases may go undiagnosed. In some cases a deletion is not present but there is a change in a gene called TBX1.

What are the symptoms of 22q11.2 deletion?

Children with 22q11.2 deletion syndrome can have a wide range of signs and symptoms, with differing degrees of severity. Some babies show signs of the condition at birth and others are diagnosed in the first few years of life.

Common symptoms include:

  • heart problems
  • low muscular tone
  • speech difficulties
  • middle ear infections or hearing loss
  • vision problems
  • feeding problems
  • frequent infections
  • learning disorders, especially with visual materials
  • developmental delays
  • communication and social interaction problems
  • psychiatric issues

Facial features may include:

  • small ears with squared upper ear
  • hooded eyelids
  • cleft palate
  • asymmetric facial appearance when crying
  • small mouth, chin and side areas of the nose tip