Angelman Syndrome – Causes, Symptoms And Treatment
Angelman Syndrome is a genetic disorder caused by a fault in chromosome 15. There are many ways to treat the disorder but unfortunately, there are no proven methods to cure it. However, researchers are continuing to search for ways to permanently cure the disease. Angelman Syndrome, sometimes called AS for short was once known as ‘happy puppet’ because of the patient’s sunny outlook and jerky movements. It was later renamed after Harry Angelman, the physician who pioneered investigation into symptoms of the disease in 1965. AS causes developmental delay and neurological problems, and can affect any person regardless of their race, gender, or age.
Angelman Syndrome is usually not recognized at birth or in infancy since the developmental problems are nonspecific during this time. Parents may begin to suspect the diagnosis after reading about AS or meeting a child with the condition. The most common age of diagnosis is between three and seven years of age, when the characteristic behaviors and features become most evident. A child who has Angelman Syndrome will show many symptoms, some which are omnipresent and others which can remain dormant for long periods of time.
Some symptoms that are always present include severe speech impairment, hyperactive behavior, movement or balance disorders, and developmental delay in sitting, crawling, walking, or mental retardation. Jerky marionette-type movements, stiff-legged walking, hand flapping, and unique behavior with an inappropriate happy demeanor that includes frequent laughing, smiling, and excitability are also some of the usual symptoms in a diagnosed child. Symptoms that are not always evident include having a small head, characteristic EEG abnormalities, tremulousness of the limbs, and seizures onset before three years of age. Many children with this disease will also have a protruding tongue, disturbed sleep, frequent drooling, and feeding difficulty during infancy. Microcephaly and Epilepsy are both common in children with this irreversible disorder.
There is no standard course of treatment for Angelman Syndrome because there is no known way to prevent or cure it. Treatment is mainly focused on providing physical therapy and adaptive devices to assist with gait and balance problems. Early language evaluation and intervention is also recommended. Patients with epilepsy are often prescribed anticonvulsant medications. Parents of children with AS usually find strength, valuable information, and comfort from support groups.
Occupational therapies, communication therapy, and behavioral therapies are important in allowing individuals with Angelman syndrome to reach their maximum developmental potential. Most individuals with AS will have severe developmental delays, speech limitations, and motor difficulties. However, people with this irrevokable disease can have normal life spans and generally do not show developmental regression as they age. Early diagnosis and the tailored interventions and therapies listed above can help improve the quality of life for those who were unfortunately diagnosed with this dire genetic disorder.
Angelman Syndrome is caused by an abnormal expression of a group of genes on chromosome 15. Researchers have found a very small deleted area in this chromosome in patients with AS. This deleted area contains genes that can be either activated or inactivated, depending on which parent the chromosome was inherited from. The gene for this disease is called UBE3A. When this gene is turned on, Angelman Syndrome does not occur. However when it is turned off or missing, Angelman Syndrome occurs. In patients with Angelman Syndrome, a missing UBE3A gene only occurs in the chromosome given by the mother.
For this reason, it seems that the UBE3A gene is turned on only on the chromosome inherited from mother. Researchers have also found that Angelman Syndrome is caused when a child inherits both chromosomes 15 from the father. This condition is called paternal uniparental disomy (UPD). In this case, both chromosomes have their UBE3A genes turned off. There is a control region, called the Imprinting Center (IC), which can control or turn on or off the action of the UBE3A gene. Mutations in the area of the Imprinting Center can also cause Angelman Syndrome, as well as many other genetic disorders.
Some disorders have similar or even the same symptoms as Angelman Syndrome. Therefore, when a doctor is diagnosing a patient, he/she must somehow rule out the other disorders to ensure that they will come up with a precise diagnosis. Some of the other disorders include Prader-Willi Syndrome, Cerebral Palsy, Rett Syndrome, Idiopathic Epilepsy, and Static Encephalopathy. AS is a fairly rare disorder. While an exact count of cases in the United States is not available, the Angelman Syndrome Foundation (ASF) has found around 1000 cases in the U.S. and Canada. However, the most important aspect of this disease has yet to be recognized: a cure.
In the recent years, there has been some beneficial research into the location and identification of the genes causing Angelman Syndrome. Now efforts are being directed towards examination of the precise functions of these genes. There is still much progress to be made in understanding the symptoms of this condition, particularly the communication problems and the seizure disorder. Therefore, the research is divided into two categories. One is Scientific research, which involves using laboratory techniques to find out about the basic chemical, physiological and anatomical abnormalities in the condition and aids diagnosis.
The other is Clinical research, which involves the observation and study of patients themselves. Both types of research will be vital in the quest to cure AS. It is thought to be unlikely that gene therapy will ever be able to cure Angelman Syndrome, due to the fact that some of the effects on early brain development are irreversible. Understanding of the genes involved, however, could be a valuable guide as to which drugs might be used to treat the condition. Quality clinical research can help to teach more about which therapies are particularly useful in the management of AS. There are now many centers all over the world which are involved in researching a cure. With all these ideas from major centers, as well as help from Angelman Syndrome families, researchers should be able to understand more about how the genes on chromosome 15 cause the symptoms of Angelman Syndrome.