What is Velocardiofacial Syndrome?
Velocardiofacial Syndrome (also known as VCFS) is one of the most common genetic conditions (following Down Syndrome.) VCFS is characterized by abnormal development of the pharyngeal arch during embryonic development. This defect results in abnormal development of the thymus, parathyroid glands, and certain parts of the heart.
Symptoms and presentation of VCFS vary wildly among those affected by the condition. VSFS has over 190 clinical features, which means that the syndrome has significiant variation - some people with VCFS lead normal lives while others may be highly impaired.
Although two genes - COMT and TBX1 - are associated with Velocardiofacial Syndrome, not all of the genes that cause VCFS have been identified. Most children who have VCFS are also missing a part of chromosome 22 (specific location: 22q11.2). As a result of this deletion, approximately 30 genes are missing from this chromosome.
DiGeorge Syndrome (DGS) may be diagnosed instead of VCFS. DiGeorge Syndrome results from the same gene deletion as VCFS; the difference in diagnosis depends upon the treating physician and the focused collection of symptoms present.
The 22q11.2 deletion syndrome has gone by many other names during the evolution of the disease, including: onotruncal anomaly face syndrome (CTAF), Opitz G/BBB syndrome, and Cayler cardiofacial syndrome. All of these syndromes have the 22q11.2 deletion in common.
Is Velocardiofacial Syndrome Inherited?
In most cases of Velocardiofacial Syndrome and DiGeorge Syndrome, neither parent has the 22q11.2 deletion. The 22q11.2 deletion occurs at some point either when the ova meets the sperm or sometime during very early fetal development. This means that the chance that the couple will have another child with 22q11.2 deletion is close to zero. It's still suggested that parents of a child with the deletion undergo genetic testing and meet with a genetic counselor prior to becoming pregnant again.
Once the deletion is present in a person, they have a fifty percent chance of having a child with the deletion.
In less than ten percent of cases of Velocardiofacial Syndrome, the chromosomal deletion is passed down through a parent. But when the deletion is hereditary, it's likely that other people in the family are affected, as well. It's suggested that parents of children with the deletion undergo genetic testing to see if they, too, have the deletion, as some cases of Velocardiofacial Syndrome have symptoms so mild as to not be noticed.
What Are The Symptoms of Velocardiofacial and DiGeorge Syndrome?
There is a great spectrum of symptoms that are associated with Velocardiofacial Syndrome and DiGeorge Syndrome, although it's worth noting that individuals do not typically have all of the following symptoms.
The most common symptoms are learning disabilities, congenital heart defects, speech and palate problems, similar facial features.
- Cleft Palate - generally occurring in the soft palate, the roof of the mouth closest to the throat.
- Congenital Heart Defects - tetralogy of Fallot, vascular rings, interrupted aortic arch, ventricular septal defects
- Striking facial structure - wide nose, small ears, long face, almond-shaped eyes
- Eye problems
- Otitis Media - middle ear infections
- Tapered fingers
- Problems feeding (due to palate malformations) - including nasal regurgitation
- Severe immunologic dysfunction - leads to difficulty fighting infections
- Genitourinary anomalies - kidney malformations and/or impaired functioning of kidneys
- Low muscle tone
- Hypoparathyroidism - low levels of parathyroid hormone
- Seizures - due to hypoparathyroidism
- Bone abnormalities in neck or back - including scoliosis
- Non-verbal learning disabilities
- Difficulties with math and abstract reasoning
- Communication and social interaction difficulties (like autism)
- (as adults) Mental Illness - Anxiety, Depression, or Schizophrenia
Diagnosis of Velocardiofacial or DiGeorge Syndrome:
Typically physical characteristics or the presence of cardiac defects will cause a physician to perform further testing. The majority of cases are diagnosed during infancy and in the early school years. Individuals presenting with cardiac problems may be diagnosed with DiGeorge Syndrome, while those with facial abnormalities such as cleft palate may be diagnosed with Velocardiofacial Syndrome.
After a clinical examination is performed to assess symptom, a blood test called a FISH (florescence in situ hybridization) will be performed to look for the deletion in chromosome 22q11.2. The deletion is present in more than 95% of children with Velocardiofacial Syndrome.
In the event that an individual does not have the deletion in chromosome 22q11.2 - instead having a smaller deletion - other laboratory studies, such as MLPA, additional FISH studies, or comparative genomic hybridization may be performed.
Chest radiography may reveal a heart defect.
An echocardiogram is necessary to rule out a heart defect, even in the absence of a heart murmur.
Renal ultrasounds are used to diagnose kidney abnormalities.
If a severe developmental delay is noted, brain MRI may be used to determine which (if any) brain abnormalities are present.
How is Velocardiofacial Syndrome Treated?
Treatment is based upon the type of symptoms a patient with Velocardiofacial or DiGeorge Syndrome exhibits. The treatment plan is as varied as the spectrum of symptoms that the person with VCFS exhibits.
Children with congenital heart defects are treated by a pediatric cardiologist.
Cleft palates should be repaired via surgical management, then managed by speech therapists to assist in speech delays.
Children with lowered immune systems should be aggressively treated with antibiotics for any infections.
Those with low calcium levels should be treated with calcium supplements (often combined with Vitamin D to aid in absorption).
Early intervention and speech therapies should be started if possible at one year of age to diagnose, assess, and treat any developmental delays.
Prognosis for Velocardiofacial Syndrome:
With proper medical management of cardiac and/or immune system problems, most children diagnosed with Velocardiofacial Syndrome will survive and grow into adulthood. A very small percentage of children born with severe heart defects and/or immune system dysfunction will not survive the first year of life.
Individuals with VCFS and DGS may require extra help throughout school and may need long-term care.
Additional Velocardiofacial Syndrome Resources:
International 22q11.2 Deletion Syndrome Foundation - information, resources, and help for families affected by Velocardiofacial Syndrome.
The Velo-Cardio-Facial Syndrome Educational Foundation, Inc. is an organization comprised of both professional and lay people whose purpose is to educate the public, the scientific community, families of individuals with Velo-Cardio-Facial syndrome, and individuals with Velo-Cardio-Facial syndrome (VCF) about this common genetic disorder.
Chromosome 22 Central - parent-run organization offering basic information and parental support about the main 22 chromosome disorders.
FACES: National Craniofacial Association - a non-profit organization serving children and adults throughout the United States with severe craniofacial deformities resulting from birth defects, injuries, or disease.
VCFS Connect is a Midwest-based support community for families dealing with VCFS and DGS.