Angelman syndrome is a genetic disorder. It causes delayed development, problems with speech and balance, intellectual disability, and sometimes, seizures.
People with Angelman syndrome often smile and laugh frequently, and have happy, excitable personalities.
Developmental delays, which begin between about 6 and 12 months of age, are usually the first signs of Angelman syndrome. Seizures may begin between the ages of 2 and 3 years old.
People with Angelman syndrome tend to live close to a normal life span, but the disorder can't be cured. Treatment focuses on managing medical, sleep and developmental issues.
Angelman syndrome signs and symptoms include:
People who have Angelman syndrome may also show the following features:
Most babies with Angelman syndrome don't show signs or symptoms at birth. The first signs of Angelman syndrome are usually developmental delays, such as lack of crawling or babbling, between 6 and 12 months.
If your child seems to have developmental delays or if your child has other signs or symptoms of Angelman syndrome, make an appointment with your child's doctor.
Angelman syndrome is a genetic disorder. It's usually caused by problems with a gene located on chromosome 15 called the ubiquitin protein ligase E3A (UBE3A) gene.
You receive your pairs of genes from your parents — one copy from your mother (maternal copy) and the other from your father (paternal copy).
Your cells typically use information from both copies, but in a small number of genes, only one copy is active.
Normally, only the maternal copy of the UBE3A gene is active in the brain. Most cases of Angelman syndrome occur when part of the maternal copy is missing or damaged.
In a few cases, Angelman syndrome is caused when two paternal copies of the gene are inherited, instead of one from each parent.
Angelman syndrome is rare. Researchers usually don't know what causes the genetic changes that result in Angelman syndrome. Most people with Angelman syndrome don't have a family history of the disease.
Occasionally, Angelman syndrome may be inherited from a parent. A family history of the disease may increase a baby's risk of developing Angelman syndrome.
Complications associated with Angelman syndrome include:
In rare cases, Angelman syndrome may be passed from an affected parent to a child through defective genes. If you're concerned about a family history of Angelman syndrome or if you already have a child with the disorder, consider talking to your doctor or a genetic counselor for help planning future pregnancies.
Your child's doctor may suspect Angelman syndrome if your child has developmental delays and other signs and symptoms of the disorder, such as problems with movement and balance, a small head size, flatness in the back of the head, and frequent laughter.
A definitive diagnosis can almost always be made through a blood test. This genetic testing can identify abnormalities in your child's chromosomes that indicate Angelman syndrome.
A combination of genetic tests can reveal the chromosome defects related to Angelman syndrome. These tests may review:
There's no cure for Angelman syndrome. Research is focusing on targeting specific genes for treatment. Current treatment focuses on managing the medical and developmental issues.
A multidisciplinary team of health care professionals will likely work with you to manage your child's condition. Depending on your child's signs and symptoms, treatment for Angelman syndrome may involve:
Finding out that your child has Angelman syndrome can be overwhelming. You may not know what to expect. You may worry about your ability to care for your child's medical concerns and developmental disabilities. There are resources that can help.
Find a team of doctors and therapists you trust to help you with important decisions about your child's care and treatment. These professionals can also help you find local resources.
Connecting with other families facing similar challenges may help you feel less alone. Ask your child's doctor for information about local support groups and other helpful organizations.
Call your doctor if your baby or child isn't reaching expected developmental milestones or has other signs or symptoms common to Angelman syndrome. Your doctor may then refer you to a doctor who specializes in conditions that affect the brain and nervous system (neurologist).
Here's some information to help you get ready for your appointment.
Questions to ask your child's doctor include:
Questions to ask a specialist include:
Don't hesitate to ask other questions, as well.
A doctor who sees your child for possible Angelman syndrome is likely to ask you a number of questions, such as:
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