Angelman Syndrome (AS)

External Ids:

MedlinePlus Genetics: ⁴² Angelman syndrome is a complex genetic disorder that primarily affects the nervous system. Characteristic features of this condition include delayed development, intellectual disability, severe speech impairment, and problems with movement and balance (ataxia). Most affected children also have recurrent seizures (epilepsy) and a small head size (microcephaly). Delayed development becomes noticeable by the age of 6 to 12 months, and other common signs and symptoms usually appear in early childhood.Children with Angelman syndrome typically have a happy, excitable demeanor with frequent smiling, laughter, and hand-flapping movements. Hyperactivity and a short attention span are common. Most affected children also have difficulty sleeping and need less sleep than usual.With age, people with Angelman syndrome become less excitable, and the sleeping problems tend to improve. However, affected individuals continue to have intellectual disability, severe speech impairment, and seizures throughout their lives. Adults with Angelman syndrome have distinctive facial features that may be described as "coarse." Other common features include unusually fair skin with light-colored hair and an abnormal side-to-side curvature of the spine (scoliosis). The life expectancy of people with this condition appears to be nearly normal.

MalaCards based summary: Angelman Syndrome, also known as as, is related to prader-willi syndrome and angelman syndrome due to imprinting defect in 15q11-q13, and has symptoms including constipation, seizures and tremor, limb. An important gene associated with Angelman Syndrome is UBE3A (Ubiquitin Protein Ligase E3A), and among its related pathways/superpathways are Prader-Willi and Angelman syndrome and Miscellaneous transport and binding events. The drugs Carbidopa and Levodopa have been mentioned in the context of this disorder. Affiliated tissues include tongue, eye and skin, and related phenotypes are eeg abnormality and ataxia

NINDS: ⁵² Angelman syndrome (AS) is a genetic disorder that causes neurological and psychological problems including seizures, difficult behaviors, movement disorders, and sleep problems.  Gastrointestinal, orthopedic, and eye problems also are often present.  Infants with AS appear normal at birth but often have feeding problems in the first months of life and exhibit noticeable developmental delays by 6-12 months.  Seizures often begin between 2-3 years of age and occur in 80-85 percent of those with AS.  Features that help define the syndrome include very happy demeanor with frequent laughter, poor balance, tremor, and minimal to no speech.  The disorder results from the absence of the UBE3A gene inherited from the mother.  The gene provides instructions for a protein that plays a critical role in the normal development and function of the nervous system. There are four types of Angelman syndrome involving problems with chromosomes or mutations in the UBE3A gene.  Other children may have a genetic syndrome that looks like AS but is caused by a different gene.  Dr. Harry Angelman first reported the syndrome in 1965, when he described three children in his practice with similar symptoms.

OMIM®: ⁵⁷ Angelman syndrome is a neurodevelopmental disorder characterized by mental retardation, movement or balance disorder, typical abnormal behaviors, and severe limitations in speech and language. Most cases are caused by absence of a maternal contribution to the imprinted region on chromosome 15q11-q13. Prader-Willi syndrome (PWS; 176270) is a clinically distinct disorder resulting from paternal deletion of the same 15q11-q13 region. In addition, the chromosome 15q11-q13 duplication syndrome (608636) shows overlapping clinical features. Clayton-Smith and Pembrey (1992) provided a review of Angelman syndrome. Cassidy and Schwartz (1998) reviewed the molecular and clinical aspects of both Prader-Willi syndrome and Angelman syndrome. Horsthemke and Wagstaff (2008) provided a detailed review of the mechanisms of imprinting of the Prader-Willi/Angelman syndrome region. Van Buggenhout and Fryns (2009) provided a review of Angelman syndrome and discussed genetic counseling of the disorder, which can show a recurrence risk of up to 50%, depending on the underlying genetic mechanism. (105830) (Updated 08-Dec-2022)

GARD: ¹⁹ Angelman syndrome is a genetic disorder that primarily affects the nervous system. Characteristic features of this condition include developmental delay, intellectual disability, severe speech impairment, problems with movement and balance (ataxia), epilepsy, and a small head size. Individuals with Angelman syndrome typically have a happy, excitable demeanor with frequent smiling, laughter, and hand-flapping movements. Many of the characteristic features of Angelman syndrome result from the loss of function of a gene called UBE3A. Most cases of Angelman syndrome are not inherited, although in rare cases a genetic change responsible for Angelman syndrome can be inherited from a parent.

UniProtKB/Swiss-Prot: ⁷³ A neurodevelopmental disorder characterized by severe motor and intellectual retardation, ataxia, frequent jerky limb movements and flapping of the arms and hands, hypotonia, seizures, absence of speech, frequent smiling and episodes of paroxysmal laughter, open- mouthed expression revealing the tongue.

Disease Ontology: ¹¹ A syndrome that is characterized by delayed development, intellectual disability, severe speech impairment, and problems with movement and balance.

Orphanet: ⁵⁸ A neurogenetic disorder characterized by severe intellectual deficit and distinct facial dysmorphic features.

Wikipedia: ⁷⁵ Angelman syndrome or Angelman's syndrome (AS) is a genetic disorder that mainly affects the nervous... more...

Clinical features from OMIM®:

Search NIH Clinical Center for Angelman Syndrome