Angelman syndrome is a rare neurogenetic disorder that impairs brain development and function. It’s typically diagnosed in early childhood and results in extensive developmental delays, intellectual disability, and speech and motor impairments.

Children with the syndrome tend to have a smiling and laughing face, with a happy disposition—features that distinguish it from other neurodevelopmental disorders. For NEET PG medical students, it is essential to know about Angelman syndrome because it integrates genetics, neurology, and paediatric medicine into a single case. 

Keep reading to understand the Angelman syndrome symptoms, causes, and treatment methods in detail for a better clinical understanding.

What is Angelman Syndrome?

Angelman syndrome is a neurogenetic condition that mainly involves the nervous system and results from defects in the UBE3A (Ubiquitin Protein Ligase E3A) gene on chromosome 15. It causes severe developmental delay, profound speech impairment, gait and balance disturbances (ataxia), and intellectual disability.

Although the condition is not fatal and life expectancy approaches normal, individuals with Angelman syndrome need lifelong assistance and therapy to control symptoms.

What are the Symptoms of Angelman Syndrome?

Here are several signs and symptoms that are frequently linked to Angelman syndrome:

• Impaired intellectual capacity
• Delays in development, including the inability to babble or crawl by 6 to 12 months
• Inability to speak or limited speech with very few words
• Difficulty with movement, balance, or walking
• Struggles with falling asleep and maintaining sleep
• A cheerful and too energetic personality
• Challenges with feeding or sucking
• A big tongue (macroglossia)
• A small head (microcephaly)
• A large lower jaw (mandibular prognathia)
• Frequent giggling and smiling
• Seizures, which typically begin between the ages of 2 and 3
• A flattened back of the head and a smaller head size
• Light-coloured eyes, hair, and skin
• Sleeping difficulties
• Presence of scoliosis or curvature of the spine

What are the Causes of Angelman Syndrome?

Angelman syndrome is a neurogenetic disorder characterised by specific genetic changes. The most common causes include the following:

• It is most often the result of a missing or defective UBE3A gene on chromosome 15, which is necessary for proper brain development.
• For some areas of the brain, only the maternal allele of the UBE3A gene is expressed; if that allele is lost or mutated, the gene is inactivated in those parts of the brain.
• In a few cases, two copies of the paternal chromosome 15 are inherited, resulting in the absence of an active maternal copy.
• There are some instances where there are unidentified genetic mutations unrelated to the UBE3A gene.
• The majority of instances happen sporadically and are non-inherited, but a few may be associated with family background.

How to Diagnose Angelman Syndrome?

Angelman syndrome is generally diagnosed on the basis of developmental issues and confirmed with genetic tests. This is how the diagnosis is done:

• The diagnosis is usually done if a child displays developmental delay, restricted or no speech, seizures, balance and movement disorders, or microcephaly (small head).
• Genetic testing via blood sample is the routine diagnostic method and can identify chromosomal defects associated with the condition.
• A DNA (deoxyribonucleic acid) methylation test can typically be used to screen for three of the four primary genetic causes of Angelman syndrome by examining parental DNA patterns.
• If the initial testing is not conclusive, a UBE3A gene sequencing test can be performed to detect subtle mutations in the mother’s gene that regular testing might not detect.
• An EEG (electroencephalogram) can also be performed to investigate brain activity, particularly if seizures are present, as they develop in Angelman syndrome.
• A chromosomal microarray (CMA) test can be employed to identify deletions of chromosome 15 segments that are frequently present in the syndrome.
• In other instances, the risk of Angelman syndrome may be detected before birth through Non-invasive Prenatal Screening (NIPS), which screens foetal DNA in a mother’s blood.

How to Treat Angelman Syndrome?

There is currently no cure for Angelman syndrome. However, individuals with this condition can enjoy quality lives. It may be necessary to adopt certain approaches to manage several symptoms and complications. For instance, they might require:

• Anticonvulsants for seizure management
• Physical therapy to enhance balance
• Braces to assist with walking
• Speech therapy
• Communication aids, such as sign language or technological devices
• Behavioural therapy 
• Medication for feeding difficulties and constipation
• Occupational therapy to help the child gain independence and manage daily tasks
• Supportive back, ankle, or foot braces
• Administering medications to facilitate food movement through the child’s gastrointestinal system
• Dietary adjustments and medications to address issues like feeding difficulties and constipation.

FAQs about Angelman Syndrome

1. When is Angelman syndrome identified?

Most kids with Angelman syndrome are diagnosed between 9 months and 6 years old, as physical and behavioural symptoms start to show. If a child is diagnosed with Angelman syndrome, consult a geneticist about the support they may require.

2. What is another term for Angelman syndrome?

Angelman syndrome was also known as ‘happy puppet syndrome’ because of the child’s cheerful face and uncoordinated limbs. It has now been given the name Angelman syndrome in memory of Dr. Harry Angelman, who first examined the symptoms in 1965.

3. What is the risk of having another child with Angelman syndrome?

For the vast majority of families, the risk is low—approximately 1 in 15,000 to 1 in 20,000. With a child having the UBE3A mutation type of AS, however, the risk goes up to approximately 1 in 2. It’s particularly important to determine the genetic type and to see a geneticist for advice if you are having further children or are already pregnant.

4. Is Angelman syndrome ever misdiagnosed?

Yes, Angelman syndrome may be misdiagnosed as its signs and symptoms usually overlap with other conditions, such as autism, cerebral palsy, or other rare genetic syndromes. Detailed clinical assessment and confirmatory genetic testing are necessary to get an accurate diagnosis.

5. What complications are involved with Angelman syndrome?

Angelman syndrome is associated with complications like feeding problems in infancy, hyperactivity, sleep disorders, scoliosis, and obesity in older children. Some become better with age, while others need medical or behavioural interventions.

Conclusion

Angelman syndrome is a rare genetic disorder with specific clinical characteristics and intricate genetic aetiologies. Though it has no cure, supportive therapy and early intervention can significantly benefit. 

For medical aspirants, particularly NEET PG candidates, comprehending disorders such as Angelman syndrome involves more than textbook reading—it calls for conceptual clarity and clinical judgment. DocTutorials provides unique NEET PG study materials that ease even the toughest concepts. 
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