About Angelman Syndrome
Traits & Symptoms
Common Angelman Syndrome Traits
Angelman syndrome symptoms often become apparent within the first year of life. While pregnancy, birth, and the newborn period are typically uneventful, developmental delays usually are noticed by 6 and 12 months of age. These early signs may prompt further investigation into potential causes, including Angelman syndrome.
Most babies living with Angelman syndrome have:
Typical pregnancy and birth
Typical size at birth
No major birth defects
Delays in their development, which become noticeable by 6-12 months of age
Other Common Angelman Syndrome Symptoms
It is also common for a baby living with Angelman syndrome to have:
Low muscle tone (hypotonia)
Difficulty feeding (suck/swallowing disorder)
Pale eye and skin color compared to family background (hypopigmentation, only seen in those with a deletion)
Most children and adults living with Angelman syndrome also share these symptoms:
Movement or balance difficulties, resulting in difficulties walking and using the hands
Severe speech impairment, with limited to no use of words
Receptive language (understanding what is said) and nonverbal communication (using gestures) abilities that are often better than their speaking ability
Unique behaviors, including frequent laughter and smiling, an apparently happy demeanor, excitability, hand-flapping, short attention span, or excessive movement (hypermotoric)
It is also common for a child or adult living with Angelman syndrome to have:
Slower head growth, which may result in a small head size compared to their body size
Seizures, usually starting before age 3
Chewing and mouthing behaviors
Difficulty with eye muscle control, causing lazy eye or eye crossing (strabismus)
Fascination or obsession with water
Walking with a wide-based gait and ankles turning out
Scoliosis (curving of the spine)
Constipation (difficulty with bowel movements)
Difficulties sleeping with disrupted sleep and abnormal sleep-wake cycles
What Causes Angelman Syndrome?
Angelman syndrome is caused by a difference on chromosome 15, specifically involving the UBE3A gene. The UBE3A gene codes for the UBE3A protein. This protein plays a critical role in brain development and function. Lack of functional UBE3A protein leads to the neurological symptoms associated with AS. Most often, Angelman syndrome is not inherited, but the exact chances for AS to run in the family depend on the genetic cause, called genotype. Understanding how the absence of UBE3A causes the symptoms of Angelman syndrome can help advance the development of potential therapeutic interventions.
Are you wondering if your loved one might live with Angelman syndrome?
If you are wondering if a loved one could have AS, or are beginning to see symptoms common in Angelman syndrome, you could start by talking with that individual’s primary care doctor. Sometimes a primary care provider like a pediatrician can order the initial testing, while other times the primary care provider will recommend your loved one see a specialist like a geneticist or neurologist.
Because the symptoms of AS can overlap with other conditions, the diagnosis of Angelman syndrome is usually made based on genetic testing, rather than on just symptoms alone. The testing for Angelman syndrome is very complicated. Because there are different genetic mechanisms that cause AS, there are multiple genetic tests that are required to confirm or rule out the diagnosis. Many of the genetic tests used to diagnose AS are not routinely ordered by primary care doctors, and they may require insurance pre-determination or pre-authorization. Consequently, seeing a genetic or neurology specialist before having genetic testing is very common. To learn more about genetic testing for Angelman syndrome, click here: https://cureangelman.org/testing-and-diagnosis
The most common symptom in babies living with Angelman syndrome is developmental delays. But many genetic conditions and other health issues can cause developmental delays. Sometimes developmental delays associated with health issues improve over time so your loved one’s doctor may recommend you “wait and see” prior to starting genetic testing, to monitor if additional symptoms develop or if the developmental delays continue. Because developmental delays are common and development varies from baby to baby, getting to a diagnosis of Angelman syndrome before age 2 can be difficult.
If you have a child between the ages of 3 and 12 months in the United States, your child may be eligible for free genetic testing and counseling through Project FIND-OUT. Click here to learn more: https://projectfindout.org/