Reducing Your Risk of Having a Child With Angelman Syndrome

You may have concerns about the risk of having a child with Angelman syndrome, especially if you have a family history of the disease, including an older child with this disease.

The majority of cases occur through spontaneous mutations in families with no history of Angelman syndrome. Still, there some steps you may want to consider in lowering the risk.

How does a child inherit Angelman syndrome?

Changes in the expression of the ubiquitin protein ligase E3A (UBE3A) gene cause Angelman syndrome.

Normally, everyone inherits two copies of every gene (one from each parent). However, the genes that we inherit from our parents are “marked” or “labeled” through a process called parental imprinting. These “labels” signal to cells which genes they should turn on or off. For example, some areas of the brain only express the maternal copy of the UBE3A gene. This is because the paternal copy is silenced.

Mutations in the UBE3A gene, or deletions of portions of the chromosome that contains the gene can cause Angelman syndrome. There is at least one known case of a woman with Angelman syndrome passing her gene mutation to her child.

Imprinting errors can also cause both copies of the UBE3A gene to be silenced, instead of only the paternal copy.

In some cases, children may inherit two copies of the UBE3A gene from their father, meaning that there is no maternal copy of the gene to express.

In 10% to 15% of Angelman syndrome cases, the cause of the disease is not known.

Prenatal diagnosis

If you choose to conceive naturally, you can request a genetic test of the fetus. This is called a prenatal genetic diagnosis. Doctors use two main methods to obtain DNA from the fetus in the womb for a genetic test: amniocentesis or chorionic villus sampling (CVS).

Each procedure has its pros and cons, and your doctor can advise you as to whether there are particular risks in your case with either procedure. Remember that genetic testing will not be able to identify about 10% to 15% of Angelman syndrome cases.

Following genetic testing, your doctor will discuss the results of the test with you. This will allow you to make decisions moving forward.

Pre-implantation genetic diagnosis

Pre-implantation genetic diagnosis is a process by which clinicians can screen an embryo created by in vitro fertilization (IVF) for genetic diseases prior to implantation. A small study indicated that conceiving via IVF could slightly increase the chances that an imprinting error will occur.

Doctors can implant only those embryo showing no sign of Angelman syndrome in the mother’s uterus. The process creates more embryos than doctors can implant. So you can also choose to freeze some for future attempts at pregnancy.

Last updated: Aug. 24, 2020

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Angelman Syndrome News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.