Angelman syndrome is a genetic disorder. It's most often caused by problems with a gene located on chromosome 15 called the UBE3A gene.
Genes are segments of DNA that provide the blueprints for all of your characteristics. You receive your genes, which occur in pairs, from your parents. One copy comes from your mother (maternal copy) and the other copy comes from your father (paternal copy).
A missing or defective gene
Both genes in a pair usually are active. This means that information from both the maternal copy and the paternal copy of each gene pair are used by your cells. But in a small number of genes, only one copy of a gene pair is active. The activity of each gene copy depends on whether it was passed from your mother or from your father. This parent-specific gene activity is called imprinting. In these genes, when the copy that is usually active is missing or defective, it causes problems in the functions and characteristics controlled by that gene.
Normally, only the maternal copy of the UBE3A gene is active in the brain. Most cases of Angelman syndrome occur when part of the maternal chromosome 15, which contains this gene, is missing or damaged. In a small number of cases, Angelman syndrome is caused when two paternal copies of the gene are inherited, instead of one paternal and one maternal copy (paternal uniparental disomy).
With no serious complications life expectancy can be the same of a normal person.
What is Angelman Syndrome?
Angelman syndrome is a genetic disorder that causes developmental delay and neurological problems. The physician Harry Angelman first delineated the syndrome in 1965, when he described several children in his practice as having "flat heads, jerky movements, protruding tongues, and bouts of laughter." Infants with Angelman syndrome appear normal at birth, but often have feeding problems in the first months of life and exhibit noticeable developmental delays by 6 to 12 months. Seizures often begin between 2 and 3 years of age. Speech impairment is pronounced, with little to no use of words. Individuals with this syndrome often display hyperactivity, small head size, sleep disorders, and movement and balance disorders that can cause severe functional deficits. Angelman syndrome results from absence of a functional copy of the UBE3A gene inherited from the mother.
Is there any treatment?
There is no specific therapy for Angelman syndrome. Medical therapy for seizures is usually necessary. Physical and occupational therapies, communication therapy, and behavioral therapies are important in allowing individuals with Angelman syndrome to reach their maximum developmental potential.