Angelman Syndrome: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Angelman Syndrome?
A pediatric neurologist (a children's brain and nerve doctor) usually leads the care, often with a medical geneticist (a doctor who studies inherited conditions). Speech, physical, and occupational therapists also help. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is Angelman syndrome?
Angelman syndrome is a genetic disorder that primarily affects the nervous system. It is present from birth. Delayed development is usually noticed at about 6 to 12 months of age. Most children have severe speech impairment, problems with movement and balance (called ataxia), and seizures. Children are typically happy and excitable, with frequent smiling and laughter. Life expectancy is close to normal.
Symptoms
Most children show no symptoms at birth. Signs usually appear in early childhood. Common symptoms include:
- Little or no speech.
- Delayed walking. The average age of walking is between 2.5 and six years.
- Jerky or stiff walking, with the legs kept wide based.
- Seizures (sudden bursts of uncontrolled brain activity). They happen in up to 90% of people and usually start before age three.
- A small head size (microcephaly).
- Sleep problems: waking often and needing less sleep than usual.
- Hyperactivity, a short attention span, and hand-flapping movements.
- Feeding problems, reflux (heartburn), and constipation.
Some children have fair skin and light hair compared with their family. Facial features can include a wide mouth and widely spaced teeth.
Causes and who gets it
Angelman syndrome happens when a gene called UBE3A does not work the way it should. People normally inherit one copy of this gene from each parent. In nerve cells of the brain, only the copy from the mother is active. This is caused by genomic imprinting. It is a natural process that switches one parent's copy off. If the mother's copy is missing or changed, most parts of the brain have no active copy of the gene.
About 70 percent of cases come from a missing segment of the mother's chromosome 15. That chromosome carries the UBE3A gene. About 10 to 20 percent come from a change in the mother's copy of the UBE3A gene. In a small number of cases, a child inherits two chromosome 15 copies from the father and none from the mother. In 10 to 15 percent the cause is not yet known. The condition affects about 1 in 12,000 to 20,000 people. Most cases are not inherited. They happen by chance. Affected people typically have no family history of the disorder.
How doctors diagnose it
Doctors look for the telltale signs, like a happy manner, little speech, and jerky movement. Genetic testing is used to confirm the diagnosis. The first test is usually DNA methylation testing (a test that checks chemical marks on the gene). It finds about 80 percent of cases. If it is normal, UBE3A gene sequencing (reading the gene's code) finds about 11 percent more. An EEG (a test that records brain waves) shows a characteristic pattern of large, slow spike waves in more than 80 percent of people. A brain MRI (a scan that takes detailed pictures of the brain) may also be done.
Treatment
There is no cure for Angelman syndrome. Treatment helps to manage health and development problems caused by the condition. Anticonvulsant (anti-seizure) medicines help control seizures. Behavior therapy helps manage hyperactivity, sleep problems, and development problems. Occupational and speech therapy manage speech problems and teach living skills. Physical therapy helps with walking and movement problems. Speech therapy can include nonverbal tools like picture cards and communication boards. Doctors also treat reflux and constipation. They check the spine for scoliosis (a curve in the spine) each year.
When to see a doctor
Contact your doctor if your child shows any sign of this condition, such as slow development, little speech, or jerky movements. Seizures can become an emergency. Call 911 or get help right away if a seizure lasts too long or does not stop. Also get help if your child becomes less aware or alert. Children with a seizure history may need rescue medicine at home for prolonged seizures.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. That doctor can track growth, sleep, feeding, and general health between specialist visits. Keeping one doctor who knows the whole picture helps the family manage long-term care.
Common questions
Is Angelman syndrome inherited?
Most cases are not inherited. The genetic change happens by chance during the formation of eggs or sperm, or early in development. In rare cases the change runs in families. A genetic counselor (a doctor or counselor who explains inherited conditions) can help parents understand their risks.
Can people with Angelman syndrome live a normal lifespan?
Life expectancy is close to normal. Many people with Angelman syndrome have friendships and take part in social life. They cannot live on their own, but they may learn certain tasks and live with others in a supervised setting.
What tests confirm Angelman syndrome?
Genetic testing confirms it. DNA methylation testing is usually the first test and finds about 80 percent of cases. UBE3A gene sequencing finds more, and an EEG can show a characteristic brain wave pattern.
Sources
- MedlinePlus Genetics - Angelman syndrome
- NCBI Bookshelf (GeneReviews) - Angelman Syndrome
- MedlinePlus Medical Encyclopedia - Angelman syndrome
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
