Patients diagnosed with Angelman syndrome will commonly present with the following signs and symptoms:

• Speech impairment
• Impaired balance
• Intellectual disability
• Developmental delays [8]
• Tremors
• Frequent smiling and laughing [9]
• Seizures
• Involuntary jerking movements
• Microcephaly
• Strabismus
• Tongue thrusting
• Hypopigmentation of the skin
• Walking with arms up in the air

• Epilepsy

  RESULTS: All patients with AS based on a deletion had epilepsy. Epilepsy was present in 3/4 children with UBE3A mutation, and 4/5 with pUPD. Onset of epilepsy occurred earlier in deletion cases compared to pUPD or UBE3A mutations cases. [ncbi.nlm.nih.gov]

  This condition is a neurogenetic disorder characterised by developmental delay, absence of speech, motor impairment, epilepsy and a peculiar behavioural phenotype. [amazon.co.uk]

• Developmental Disorder

  Angelman syndrome is a neuro-developmental disorder caused by genetic abnormalities affecting the maternal gene expression in the chromosome region 15q11-q13. [ncbi.nlm.nih.gov]

  Since Angelman syndrome is a developmental disorder, it is crucial to include younger patients in the testing of treatments, Ovid said. A development disorder is one that impairs a person’s development in childhood. [angelmansyndromenews.com]

  […] as a whole,[130] although prevalence rates vary for each of the developmental disorders in the spectrum. [en.wikipedia.org]

  Nigro and Thomas Pittman, Developmental Disorders, Atlas of Clinical Neurology, 10.1007/978-1-57340-359-7_1, (1-34), (2009). [doi.org]

• Impaired Balance

  Patients diagnosed with Angelman syndrome will commonly present with the following signs and symptoms: Speech impairment Impaired balance Intellectual disability Developmental delays Tremors Frequent smiling and laughing Seizures Involuntary jerking movements [symptoma.com]

  Ataxia (impaired balance or coordination). Seizures. Facial features of Angelman syndrome Common facial features of Angelman syndrome include: A short and broad skull (brachycephaly). [my.clevelandclinic.org]

• Widely Spaced Teeth

  Wide mouth. Protruded tongue. Widely spaced teeth. Open bite. Orofacial/odontological symptoms There is a particular appearance characteristic for the diagnosis. [mun-h-center.se]

  The physical "prototype" includes microcephaly with flat neck, fair skin and hair, wide-spaced teeth, and open mouth with tongue protrusion. Epilepsy is characterized by atypical absences, erratic myoclonus, and occasional tonic-clonic seizures. [ncbi.nlm.nih.gov]

  Less universal findings of Angelman syndrome include: microcephaly flat neck pale skin and fair hair widely spaced teeth tongue protrusion and open mouth scoliosis constipation feeding difficulties. [news-medical.net]

• Macrostomia

  Most patients of this age group show at least 8 of the major characteristics (bursts of laughter, happy disposition, hyperactive behaviour, microcephaly, brachycephaly, macrostomia, tongue protrusion, mandibular prognathism, widely spaced teeth, stiff [ncbi.nlm.nih.gov]

  […] age, absent speech (or speech limited to less than six words), jerky movements with an ataxic gait if the patient is walking, paroxysm of inappropriate laughing, dysmorphic craniofacial features (brachycephaly, mid-facial hypoplasia, deep set eyes, macrostomia [pesquisa.bvsalud.org]

  […] head), ataxia, frequent jerky limb movements and flapping of the arms and hands, hypotonia (floppiness), hyperactivity, seizures, absence of speech, frequent smiling and outbursts of laughter, and an unusual facies (facial appearance) characterized by macrostomia [bibliomed.org]

  Generally from 1 year of age, the typical features of AS develop: severe intellectual deficit, absent speech, outbursts of laughter with hand flapping, microcephaly, macrostomia, maxillary hypoplasia, prognathia and neurological problems with a puppet-like [orpha.net]

• Malocclusion

  Widely-spaced teeth are common, as are malocclusions in the form of a postnormal or prenormal bite and an open, frontal bite. Daytime tooth grinding is common. Many like to suck and bite their hands and objects. [mun-h-center.se]

• Sialorrhea

  […] by water, paper and plastic (+) Aggressiveness (+) Abnormal EEG patterns (+) Hypopigmentation NO Scoliosis (+) Wide mouth (+) Wide-spaced teeth (+) Prognathism NO Tongue thrusting (+) Strabismus (+) Deep-set eyes NO Upslanting palpebral fissures (+) Sialorrhea [scielo.br]

• Bruxism

  Subsequently she had bruxism and developmental regression since she was 1 year and 6 months of age with loss of some motor and social skill. [hindawi.com]

• Small Head

  Most children with Angelman syndrome have microcephaly (small head size) and epilepsy (recurrent seizures). The developmental delay of Angelman syndrome generally becomes noticeable by the age of 6 to 12 months. [medicinenet.com]

  Individuals with this syndrome often display hyperactivity, small head size, sleep disorders, and movement and balance disorders that can cause severe functional deficits. [pediatricbrainfoundation.org]

  head (microcephaly), epilepsy, severe learning difficulties (with poor communication skills and little or absent speech), an unsteady or ataxic gait, a characteristic facial appearance and a happy disposition. syndrome d'Angelman fr [gaois.ie]

• Muscle Hypotonia

  Cerebellar ataxia, muscle hypotonia and tremor, though constant in childhood, tend to be attenuated in adulthood. [ncbi.nlm.nih.gov]

  HYPOTONIA ; and a peculiar facies. [hon.ch]

  A dictionary of medical eponyms Related people Harry Angelman A chromosome 15 disorder comprising microcephaly with mental and motor retardation, epilepsy, ataxic gait or complete inability to walk, muscle hypotonia, EEG abnormalities, and peculiar [whonamedit.com]

• Easily Excitable

  Their behavior may combine frequent laughter and smiling, an easily excitable personality, hand flapping movements, hyperactive behavior, and a short attention span. [omicsonline.org]

  Behavioral uniqueness - any combination of frequent laughter/smiling, apparent happy demeanor, easily excitable personality, often with hand flapping movements. [achievementcenteroftexas.org]

  Children with Angelman syndrome may be easily excited, hypermotoric and hyperactive. They are active explorers and often may appear to be constantly in motion. [web.archive.org]

  excitable personality, often with hand flapping movements; hypermotoric behaviour; short attention span Frequent (more than 80%) Delayed, disproportionate growth in head circumference, usually resulting in microcephaly (absolute or relative) by age 2 [angelmanuk.org]

  They are easily excitable and have frequent episodes of laughter and smiling, even during inappropriate times. [pedclerk.bsd.uchicago.edu]

• Inappropriate Laughter

  Angelman syndrome is characterized by mental retardation, seizures, ataxia, inappropriate laughter, lack of speech, a particular facial appearance, and generally a chromosome 15q11-q13 deletion. [ncbi.nlm.nih.gov]

  Excessive and inappropriate laughter is a telltale sign. The actual number of cases of Angelman syndrome is unknown. Some estimates are 1 in 15,000 babies have Angelman syndrome. Others estimate 1 in 30,000. [mentalhelp.net]

  Angelman syndrome is a rare genetic disorder characterized by severe intellectual and developmental disability, sleep disorder, frequent and sometimes inappropriate laughter, seizures, jerky movements and ataxia. [symptoma.com]

• Stereotyped Behavior

  Other characteristics are hyperactivity and stereotypic behavior. Images Characteristic facial features in Angelman syndrome: Small head. Flat back of the head. Wide mouth. Protruded tongue. Widely spaced teeth. Open bite. [mun-h-center.se]

  Associated Behavioral Conditions Hyperactivity Laughter and happiness Repetitive and stereotypic behavior such as hand flapping Sleep problems [urmc.rochester.edu]

  The checklist evaluates irritability, lethargy, stereotypic behavior, hyperactivity, inappropriate speech and provides a raw score for each domain. [clinicaltrials.gov]

  Parent report of stereotyped behaviors, social interaction, and developmental disturbances in individuals with Angelman syndrome // J. Autism. Dev. Disord. — 2007 May. — 37(5). — 940-7. — doi 10.1007/s10803-006-0233-8. Williams C.A. [childshealth.zaslavsky.com.ua]

• Psychomotor Retardation

  Angelman syndrome is a neurogenetic disorder resulting in refractory epilepsy and profound psychomotor retardation in its most prevalent form, caused by deletion of maternal chromosome 15q11-13. [ncbi.nlm.nih.gov]

  The main features consist of psychomotor retardation, developmental speech disorder, ataxia, tremor, hyperactivity, clapping hands, inadequate laughter and happiness, attention deficit and epilepsy. [osti.gov]

  retardation, often accompanied by epileptic seizures, and autistic features. [en.wikipedia.org]

• Abnormal Behavior

  Angelman syndrome is a neurodevelopmental disorder characterized by mental retardation, severe speech disorder, facial dysmorphism, secondary microcephaly, ataxia, seizures, and abnormal behaviors such as easily provoked laughter. [ncbi.nlm.nih.gov]

  OMIM : 56 Angelman syndrome is a neurodevelopmental disorder characterized by mental retardation, movement or balance disorder, typical abnormal behaviors, and severe limitations in speech and language. [malacards.org]

  Animals homozygous for amorphic mutations of Dmel\Ube3a are viable and fertile, however, they have neuroanatomy abnormalities and show defects in locomotive behavior, circadian rhythms, and long-term memory. [flybase.org]

• Seizure

  By age 2-3 years, more than 80% of patients have seizures and abnormal EEGs with large amplitudes and slow spiked waves, even in the absence of active seizures. [pedclerk.bsd.uchicago.edu]

  Majority of patients with Angelman syndrome will have microcephaly and recurrent bouts of seizures that starts beyond the age of two years old. [symptoma.com]

  Seizures in AS are usually controllable with one or more anti-seizure medications. In some individuals with severe seizures, dietary manipulations may be tried in combination with medication. [encyclopedia.com]

  Seizures Seizures are present in 85% of patients within the first three years of life[ 17 ], although less than 25% develop seizures during the first year[ 18 ]. [ijponline.biomedcentral.com]

• Ataxia

  Angelman syndrome (AS) is a neurodevelopmental disorder characterized by mental retardation, speech impairment, ataxia, and happy disposition with frequent smiling. [ncbi.nlm.nih.gov]

  Friedreich’s Ataxia is the most common hereditary ataxia with an estimated 5,000 to 10,000 patients in the U.S. There are an estimated 10,000 to 15,000 people living with Angelman syndrome in the US. [businesswire.com]

  However, the cognitive and neurologic impairment is more severe in AS, including seizures and ataxia. [malacards.org]

• Tremor

  RESULTS: All patients had tremors in the limbs, head, and trunk, which resulted in 2 patients falling backward. These tremors lasted several seconds, and could emerge in clusters for hours in older patients. [ncbi.nlm.nih.gov]

• Abnormal Sleep-Wake Cycles

  Sleep disorders are also common, often characterized by abnormal sleep-wake cycles. Movement disorders are nearly universal in Angelman syndrome, most frequently presenting with ataxia and tremor. [ncbi.nlm.nih.gov]

  Other characteristics noted in over 80% of patients include microcephaly, seizures, and a specific, abnormal EEG pattern. Patients may also exhibit wide mouths with unusual tongue/mouthing behaviors, hypopigmentation, and abnormal sleep-wake cycles. [dnatesting.uchicago.edu]

  Sleep disturbances such as a decreased need for sleep and disrupted or abnormal sleep/wake cycles (e.g., awaking at night or rising earlier than normal) are frequent findings in children with Angelman syndrome. [web.archive.org]

  Sleep Sleep disorders are also common, often characterised by abnormal sleep-wake cycles. [ 6 ] The sleep disorders may be related to abnormal serum melatonin profiles. [ 7 ] Poor sleep does not significantly interfere with daytime alertness. [patient.info]

• Myoclonus

  The patient demonstrated generalized prolonged myoclonus severe enough to produce temperatures of 41.4 degrees C and CPK elevations to 7281 U/l. This myoclonus was unresponsive to benztropine, clonazepam and worsened with bromocriptine. [ncbi.nlm.nih.gov]

  Danielle M Andrade, Clement Hamani and Berge A Minassian, Treatment options for epileptic myoclonus and epilepsy syndromes associated with myoclonus, Expert Opinion on Pharmacotherapy, 10, 10, (1549), (2009). Gregor D. Gilfillan, Kaja K. [doi.org]

Children with Angelman syndrome will typically present clinically with obvious developmental delays, microcephaly, movement disorders, impaired balance, and seizure disorders. This constellation of signs and symptoms is very suggestive of the syndrome clinically. The following tests may be used to confirm the diagnosis of Angelman syndrome:

• Chromosome analysis or karyotyping: This is the direct microscopic examination of the chromosomes to determine and identify any defects in the morphology and size of the sampled chromosomes.
• Fluorescence in situ hybridization (FISH): This fluorescence assay will demonstrate the defective long arm of chromosome 15 in Angelman syndrome.
• DNA methylation test: This test reveals any gene imprinting defects by the use of methylation techniques. Angelman syndrome will show the absence of the maternal gene copy and expression within the brain tissues.
• UBE3A gene sequencing: This a specific test that demonstrates the presence of gene mutation within the maternal copy of the gene found in a chromosome subset.

• Excessive Drooling

  Additional findings include excessive drooling, crossed eyes (strabismus), lack of normal color of the (hypopigmentation) of the skin, eyes and hair due to lack of certain melanin pigments. [web.archive.org]

  drooling fast and involuntary eye movements (nystagmus) Angelman syndrome is caused by a change involving the gene E3 ubiquitin protein ligase (UBE3A). [healthline.com]

The gene defect in Angelman syndrome is irreparable; thus, there is no known cure for this rare syndrome. Treatment will only focus on the management of the medical and developmental problems of the affected child. Because of the complexity of the problems involved in Angelman syndrome, a multidisciplinary approach is often times imperative in the management of the disease. The following treatment modalities are available for Angelman syndrome:

• Anti-convulsant medications: This therapy is given to control the seizure disorders associated with Angelman syndrome. 
• Physical therapy: Patients with Angelman syndrome may learn to walk promptly and balance with the help of physical therapy and rehabilitation.
• Speech therapy: Speech therapy among patients with the syndrome may hasten communication problems. Patients may be taught sign language if verbal communication is not achieved [10].
• Behavioral therapy: This will help children with Angelman syndrome to control hyperactivity and hasten developmental delays.

The majority of patients with Angelman syndrome will have progressive developmental delay, speech dysfunctions, and motor difficulties till adulthood. However, these patients will have a normal lifespan without any developmental regression as they chronologically age. The prompt diagnosis of Angelman syndrome coupled with a customized interventional therapy and support improves the prognosis among patients. Female patients with Angelman syndrome have been observed to be prone to obesity and worsening of scoliosis [7].

Angelman syndrome results from the maternal gene deletion of the locus UBE3A located at the long arm of chromosome 15 (15q11-13) [2]. Studies have demonstrated that Angelman syndrome is closely associated with the intracytoplasmic sperm injection (ICSI) procedures with in vitro fertilization (IVF) techniques used for male infertility [3]. The genetic etiology in Angelman syndrome is brought about by the imprinting defects during the DNA gene expression of the maternal chromosome subset.

The international incidence of Angelman syndrome as a molecular gene defect is approximately 1 case per 300,000 genetic diseases. The syndrome is further evident with an overall incidence rate of 1 case per 12,000 to 20,000 population. Mothers undergoing assistive IVF hormonal steroid therapy have an increased risk of giving birth to an infant afflicted with Angelman syndrome to more than 12.5 times compared to normal unassisted births [4].

The main pathophysiology of Angelman syndrome stems out from the absence of the maternal gene contribution in the long arm of the chromosome 15 [5]. Other possible genetic causes of the syndrome include genetic translocation, uniparental disomy, and single gene mutation within the chromosome. The subsequent deletion of the gene within the long arm of chromosome 15 will result in the non-expression of the UBE3A gene needed in the DNA methylation during the ubiquitin pathway.

Recent studies have postulated that the absence of the UBE3A gene will lead to the impairment of the hippocampus memory and cognitive functioning that assists in the learning process, and the synaptic plasticity that controls movements and balance. One of the pathognomonic signs of Angelman syndrome is the characteristic electroencephalogram changes in the prefrontal leads suggesting that the pathogenesis of the syndrome could possibly be associated with some abnormalities in the neurophysiology of the brain [6].

In few cases of Angelman syndrome, there has been an observable genetic transmission pattern noted. Genetic counselling may be needed to prevent the recurrence of the disease in the family lineage.

Angelman syndrome is an uncommon genetic disorder presenting with developmental delays and neurologic impairments. Patients with Angelman syndrome are observably happy and excitable people with frequent outburst of laughter [1]. Developmental delays with this syndrome are observable between the first 6 to 12 months of life while seizure ensues around 2 to 3 years of age. Majority of patients with Angelman syndrome will have microcephaly and recurrent bouts of seizures that starts beyond the age of two years old.

Despite their coarse anatomic features and severe neurologic impairments, patients suffering from Angelman syndrome have a comparatively similar life expectancy compared to the normal population. The goal in the management of Angelman syndrome focuses on the patient’s neurological dysfunctions and developmental delays.

Definition

Angelman syndrome is a rare genetic disorder characterized by intellectual disability, developmental delay, microcephaly, speech impairment, and movement disorders.

Cause

Angelman syndrome results from the maternal gene deletion of the locus UBE3A located at the long arm of chromosome 15 (15q11-13). Some less common genetic causes include genetic translocation, uniparental disomy, and single gene mutation.

Symptoms

Patients will physically present with microcephaly, with observable speech, developmental, and movement impairments.

Diagnosis

Clinical history, physical examination and neurologic examinations may clinch the diagnosis of Angelman syndrome. Confirmatory test like karyotyping, FISH, DNA methylation tests, and gene sequencing may also be implored.

Treatment and follow-up

Patients are treated with anti-convulsant therapy, physical and speech therapy, and behavioral therapy.

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