What's 22q11.2 deletion syndrome?
22q11.2 deletion syndrome is a contiguous-gene deletion disorder: in about 85-90% of cases a heterozygous ~3-Mb deletion on chromosome 22 removes a set of genes, including TBX1, the gene most responsible for the heart defects. Confirmed by chromosomal microarray. There is no treatment that corrects the deletion; care is supportive and organ-directed (heart surgery, calcium and vitamin D for low calcium, immune monitoring and sometimes thymus transplant, and developmental and psychiatric support).
| Also indexed as | ORPHA:567, MONDO:0018923 |
|---|---|
| Features mapped | 26 |
| Treatments mapped | 1 |
| Published sources | 15 |
| Last reviewed | 2026-08-04 |
Signs and symptoms
Intellectual disability
People with this condition often have difficulty with learning and thinking skills, similar to what is seen in autism and schizophrenia.
Schizophrenia
The deletion markedly raises the lifetime risk of psychiatric illness. Schizophrenia develops in roughly one in four people with the deletion, far higher than in the general population, so mental-health monitoring is an important part of long-term care. This is a raised risk, not a certainty.
Global developmental delay
Developmental delay and later learning difficulties are common, and many children need educational and speech support.
Seizure
In some people, seizures caused by low calcium levels can be clues leading to an eventual diagnosis of 22q11.2 deletion syndrome.
Interrupted aortic arch
Interrupted aortic arch (a gap in the body's main artery, classically type B) is another characteristic heart defect that presents in the newborn period and requires urgent surgery.
Abnormal thymus morphology
Congenital athymia is characterized by thymic absence and profound T-cell immunodeficiency.
Tetralogy of Fallot
Conotruncal heart defects (those affecting the heart's outflow tract) are common, with tetralogy of Fallot being a frequent example. These often need surgical repair in infancy.
Short stature
SHOX deficiency disorders can affect growth in different ways. Some people have mild short stature, while others develop more noticeable differences in the length and shape of their arms and legs.
Thrombocytopenia
People with 22q11.2 deletion syndrome have an increased risk of immune thrombocytopenia (ITP), a condition in which the immune system attacks platelets, making it harder for blood to clot. In many cases, ITP can return after treatment or be difficult to control with standard therapies.
Parathyroid hypoplasia
DiGeorge syndrome often involves underdeveloped parathyroid glands.
Hypocalcemia
Low blood calcium (hypocalcemia) is common, especially in newborns, and can cause seizures or tetany. It stems from underactive parathyroid glands.
Decreased circulating parathyroid hormone level
The body's parathyroid glands produce less of the hormone that normally helps control calcium levels.
Seborrheic dermatitis
Seborrheic dermatitis is an inflammatory skin condition that can look similar to other skin problems but can be identified by where it appears on the body and what it looks like.
Recurrent infections
People with this condition tend to be more susceptible to infections than others without the condition.
Recurrent pneumonia
Nearly half of all people with this condition get recurrent pneumonia and ear infections.
Recurrent otitis media
People with 22q11.2 deletion syndrome often experience lifelong ear, nose, and throat problems, including frequent ear infections, speech and swallowing difficulties, airway and sleep-breathing issues, and a higher risk of complications during surgery due to other underlying medical differences.
Tetany
Low levels of parathyroid hormone can cause calcium levels to drop, leading to involuntary muscle cramps, contractions, or stiffness (tetany).
High palate
Many people with a cleft palate need surgery to correct velopharyngeal insufficiency (VPI), a condition in which the soft palate does not close properly during speech, allowing air to escape through the nose.
Cleft palate
Palate problems are common, including cleft palate and a gap in the muscular closure at the back of the throat (velopharyngeal insufficiency), which affects feeding and speech.
Autism
People with this condition often have autism-related traits that are influenced by genes also linked to autism in other conditions.
Hypoparathyroidism
The parathyroid glands, which control calcium, are often underdeveloped (hypoparathyroidism), which is the underlying reason for the low calcium and may require calcium and vitamin D treatment.
Ptosis
Researchers found that increasing FENDRR activity slowed the growth of lung cancer cells, made chemotherapy more effective, and helped trigger cancer cell death.
Immunodeficiency
Because the thymus (where T-cells mature) is small or absent, the immune system is often weakened, leading to frequent infections. The severity ranges from mild to, rarely, complete absence of the thymus requiring transplant.
Autoimmunity
Secondary and age-related thymus dysfunction can increase the risk of infections, cancer, and autoimmune diseases, in which the immune system mistakenly attacks the body’s own tissues.
Chronic otitis media
People with 22q11.2 deletion syndrome often experience ongoing ear, nose, and throat problems throughout their lives. These can include frequent ear infections, abnormal skin growth in the ear (cholesteatoma), speech and swallowing difficulties caused by problems with the roof of the mouth and throat, airway abnormalities, sleep-related breathing problems, and difficulty swallowing. They may also face higher risks during surgery because of differences in their blood vessels, immune system, and blood clotting function.
Abnormal facial shape
Characteristic facial features are part of the picture, though they can be subtle and are not present in everyone.
Treatment and management
What the research describes, not a recommendation. Treatment decisions belong with your clinician.
This covers treatments that appear in the published research mapped here. Investigational and experimental therapies are not included, so their absence is a boundary of this map, not a sign they do not exist.
calcium and vitamin D supplementation
Low blood calcium from underactive parathyroid glands is common in 22q11.2 deletion syndrome and is managed with calcium and vitamin D supplements. Care is otherwise directed at each person's specific features, such as heart defects.
Used to help with: 22q11.2 deletion syndrome.
“She was treated with moderate-dose cholecalciferol and oral calcium supplements.”
What changes how it shows up
Carrying the genetic change is not the whole story. The factors below are described in the research mapped here as changing whether, or how strongly, the condition appears. They modulate how the genotype is expressed; they do not, on their own, cause or cure it.
variable expressivity
Even with the same deletion, the features vary enormously between individuals and even within the same family. Two people with the same change can be affected very differently, which is why the deletion alone does not predict the outcome.
Described as modulating: 22q11.2 deletion syndrome.
“…characterized by an extreme intrafamilial and interfamilial…”
How to read the evidence labels
Where this comes from
This guide is built from 15 published source(s). Every claim above links back to one of them. Click any source ID to read the original on PubMed.
Take it further
Printed, source-linked documents built from this condition's graph — ready to bring to an appointment or attach to a coverage request. Every claim carries its published source, the same as this guide.