What is angelman syndrome ?
Angelman syndrome is a congenital disorder of the central nervous system which, in addition to typical behavior and facial features, there is an intellectual disability.
History and naming
Dr. Harry Angelman, an English pediatrician, described in 1965 three children with a stiff movement pattern, which could not talk, seizures were striking and laughter, had a small head and a severe learning disability. Originally called the syndrome "happy puppet syndrome. The jerky movements did dr. Angelman thinking 'puppets on a string "(puppets). Later, in 1967 the term "happy puppet syndrome 'was coined by other authors who described children with this syndrome and emphasized the cheerful countenance and the sudden laughter of these children. Due to the negative connotation of this name is spoken since 1982 on Angelman syndrome.
Angelman syndrome causes
Angelman syndrome arises, when a particular gene on the long arm of the chromosome 15 derived from the mother is not active. (This gene is on the paternal chromosome 15 in some parts of the brain namely, turned off). This situation can arise in the following manner:
- Deletion: the area where the gene is missing on the chromosome of maternal origin (70-75% of the cases).
- Uniparental paternal (father) disomy, ie by an error in cell division both chromosomes 15 are from dad. Because UBE3A on the paternal chromosome is turned off, Angelman syndrome occurs (2-5% of cases).
- Imprintingsstoornis: the gene is plotted on the maternal chromosome (2-7% of the cases).
- Gene mutation. The UBE3A gene does not function because there is a change in the DNA code has occurred.
Feature
- Severe to profound intellectual disability.
- As a child laugh / giggle; adult friendly look.
- Ataxia: stiff and uncertain locomotion.
- Absence of speech: children with Angelman syndrome learn more than 2 or 3 words to speak.
- Scoliosis.
- Epilepsy, which usually brief absences by vibrating or small shocks, occurs in 80%.
- Characteristic EEG abnormalities at the age of 2-6 years (slow waves with high voltage from occipital); these also occur in children with Angelman syndrome without epilepsy).
- Sleep disorders; light sleep and wake up soon; break melatonin slowed down.
- Microcephaly: small head circumference, especially flat head.
Wide-set teeth, big jaw. - Light hair color (blond, red) and light color eyes (blue, green); to the deletion.
Life
Pregnancy, birth and infant
For some children it behind head at birth that flat. Generally there are during pregnancy and birth are no reasons for concern. Everything seems to be normal. In the first months there is often talk of nutritional problems. The growth rate of the head is slowly decreasing. The muscle tension is often slightly reduced in the trunk (hypotonia) and increased muscle tone in the limbs something (hypertension). The development has been slow. There may be shaky or jerky movements arise from the body, thereby'll milestones such as crawling and independent often a little longer in coming. Most children with this syndrome also go running late, some children learn not to run at all. Some babies laugh remarkably. They generally make a happy and joyful impression. Around the first year of life they often get their first seizure.
Early years
Children with Angelman syndrome are remarkably quickly enthusiastic about mobile and pressure, thereby able to laugh uproariously. Sometimes they scream or shout. They are restless over, show uncontrolled movements of the body, flapping hands and have an unsteady gait during walking and running. They put a lot into their mouth (fingers, hands, toys). Often they have the tongue from the mouth and drooling them. There is a short attention span and speech development does not start. There is, depending on the severity of the intellectual disability sometimes passive comprehension present. Some children babble or even know a few words, these are often not used properly. It is in childhood quite clear that something is going on. " There is a (severe) developmental delay. Later in life they may develop an excessive interest in food. Before and certain abnormal facial features are in puberty clear: a small round head, large mouth, a thin upper lip, often the tongue from the mouth, wide-set teeth and a big jaw.
Adults
There is a (very) serious intellectual disability. Movements are usually less unchecked in adulthood. Epilepsy may disappear, but sometimes persists. If the motor deficits really are to the fore, the patient may become wheelchair dependent.