What is CHARGE Syndrome?

CHARGE syndrome is a recognizable (genetic) pattern of birth defects which occurs in about one in every 9-10,000 births worldwide. It is an extremely complex syndrome, involving extensive medical and physical difficulties that differ from child to child. The vast majority of the time, there is no history of CHARGE syndrome or any other similar conditions in the family.

Babies with CHARGE syndrome are often born with life-threatening birth defects, including complex heart defects and breathing problems. They spend many months in the hospital and undergo many surgeries and other treatments. Swallowing and breathing problems make life difficult even when they come home. Most have hearing loss, vision loss, and balance problems which delay their development and communication. All are likely to require medical and educational intervention for many years. Despite these seemingly insurmountable obstacles, children with CHARGE syndrome often far surpass their medical, physical, educational, and social expectations.

Continued research is needed to understand the medical and developmental challenges facing individuals with CHARGE. Better understanding will lead the way to interventions, therapies and educational strategies which can help people with CHARGE syndrome overcome many of the obstacles in their lives.

One of the hidden features of CHARGE syndrome is the determination and strong character these children display.

History of the name “CHARGE”

The name “CHARGE” was a clever way (in 1981) to refer to a newly recognized cluster of features seen in a number of children. Over the years, it has become clear that CHARGE is indeed a syndrome and at least one gene causing CHARGE syndrome has been discovered. The letters in CHARGE stand for:

  • Coloboma (cleft) of the eye
  • Heart defects (complex, like Tetralogy of Fallot)
  • Atresia of the choanae (passages that go from back of nose to throat)
  • Retardation of growth and/or development
  • Genital and/or urinary abnormalities
  • Ear abnormalities and deafness

Those features are no longer used in making a diagnosis of CHARGE syndrome, but the name will not change.

Clinical Diagnostic Criteria (2005)

Even though a gene for CHARGE syndrome has been discovered, the gene test is very expensive and isn’t perfect -only about 2/3 of people with CHARGE have a positive gene test. Therefore, the diagnosis of CHARGE syndrome is still clinical – based on the medical features seen in the child.

An evaluation for possible CHARGE syndrome should be made by a medical geneticist who is familiar with CHARGE. The clinical diagnosis is made using a combination of Major and Minor features. Major features are characteristics that are quite common in CHARGE syndrome but relatively rare in other conditions, and are, for the most part, diagnosable in the newborn period. Minor features are characteristics which are also common in CHARGE, but not quite as helpful in distinguishing CHARGE from other syndromes. They either are common in other conditions (e.g. heart defects), harder to diagnose consistently (e.g. typical CHARGE face), or may not be diagnosed until later (e.g. growth deficiency).

Finally, there are “Other” features – these may be very important in terms of health and management, but are not very helpful in determining if a child has CHARGE syndrome or something else.

No one feature is required to make a diagnosis of CHARGE. Every feature varies from severe to absent in different children.

What else can look like CHARGE (differential diagnosis)?

  • 22q deletion syndrome (aka VCFS, DiGeorge): can have many of the same medical features. However, the face, hands and ears look different. Special FISH test can diagnose 22q deletion
  • Kabuki syndrome: can have many of the same medical and behavioral features. The eyes and fingertips are different and puberty is early in Kabuki syndrome.
  • VATER/VACTERL association: can result in similar medical problems. The ears, face and hand do not look like CHARGE syndrome
  • Some chromosome abnormalities can have features which overlap with CHARGE syndrome
  • Retinoic embryopathy: exposure to Accutane during pregnancy can produce similar ears and heart defects – other features are different
  • PAX2 mutations can cause colobomas, hearing loss and rare kidney problems

What causes CHARGE syndrome?

CHARGE syndrome is a genetic condition, caused by a change (mutation) in a single gene, most often CHD7. In August, 2004, the first major gene for CHARGE syndrome was reported by a group of researchers in the Netherlands. The gene is CHD7, located on the long arm of chromosome #8. It is a regulatory gene which plays a role in turning other genes on and off.

Changes (mutations) in this gene have been found in more than half of all children with CHARGE tested to date. In the vast majority, the mutation was new in the child – not detected in the parents. This confirms that CHARGE syndrome is a genetic condition caused by a new mutation in a dominant gene. Further research is needed to find other genes that can cause CHARGE and to determine the function of the CHARGE genes in the developing fetus, babies, children and adults.

Source: http://www.chargesyndrome.org/