Angelman syndrome is a genetic disorder characterized by neurological and developmental abnormalities. The disease is characterized by mental retardation, trouble in walking and balancing (ataxia), absence of speech, jerky movement of hands and legs and seizures. Patient suffering from Angelman syndrome have distinct behavioral feature; they easily and frequently smile and laugh without any reason or provocation.
Dr Harry Angelman was first person to describe the syndrome in 1965. Angelman syndrome occurs due to absence of particular gene (UBE3A) located on chromosome 15. The unique feature of angelman syndrome is that it is not apparent from birth of the child, but symptoms appear gradually from 6 months onward.
Person with Angelman syndrome usually has normal life span. The disease is incurable. Treatment is focused on improving motor and cognitive skills of the patient.
What Causes Angelman Syndrome?
Angelman syndrome is a rare abnormal genetic condition. Medical fraternity does not know the cause of change in the genetic pattern. Studies suggest most people suffering from Angelman syndrome do not have any family history of this condition.
Angelman syndrome is a disorder related to genes. The ubiquitin protein ligase (UBE3A) gene located on chromosome 15 is at fault. Chromosomes are situated in each and every cell.They carry genetic information of each individual. Normally a person receives genes from his mother and father. One copy from mother and one copy from father. The cells inherit trait from both these copies.
Usually only the UBE3A copy gene from mother’s side is active in brain. But in Angelman syndrome, the maternal copy of this gene is missing or there may be structural change in it. In some patients only two paternal copies of gene is inherited instead of one from each parent. This may lead to problem in mental and developmental growth of the child.
Signs And Symptoms Of Angelman Syndrome
There is a spectrum of symptoms representing Angelman syndrome. But the individual symptoms may vary from one person to another. The symptoms usually begin from 6 to 12 months after birth. These symptoms include:
- Delay in developmental milestones such as crawling, walking, etc.
- Absence of speech or the child is able to speak only few words.
- As the child grows, he may be able to understand and communicate through gestures.
- Difficulty in balancing the body and walking. In mild cases the child may learn to walk at the age of 2 to 3. Some children may not walk till 10 years of age.
- Uncontrollable, unprovoked laughter without any reason. This distinct happy demeanor is specific of Angelman syndrome.
- Mental retardation
- Learning disability
- Hyperactive child
- Restless behavior
- Wide gait while walking
- Widely spaced teeth
- Flat occiput. The head circumference is smaller than the normal.
- Frequent protrusion of tongue.
- Epileptic seizures which usually occur at the age of 2 to 3 and mostly improve as the child becomes adolescent.
- During infancy the child finds difficulty in sucking the breast as a result there is feeding as well as swallowing problem.
- Skin, hair and eyes are light colored due to less pigmentation.
- Hand flapping and uplifting of arm while walking.
- Frequently waking up this causes disturbed sleep.
- Child with Angelman syndrome is fascinated with water and gets attracted with shiny objects.
Treatment Options For Angelman Syndrome
Angelman syndrome is incurable condition, but a person suffering from it lives his normal span of life. There are several researches taking place which are aimed in targeting the specific gene as a treatment measure. However, currently treatment paradigm is to improve cognitive and motor deficit.
- Anti seizure medications are needed for those who experience convulsion.
- If the child or adult suffers from sleep disorder, he is trained to sleep strictly at certain fixed time.
- Physical therapy is beneficial for walking and standing up.
- Scoliosis is a deformity of spine, correction may require wearing braces.
- Child suffering from Angelman syndrome requires speech and occupational therapy.
- Behavior therapy is useful to reduce hyperactivity which is very common in Angelman syndrome.