Communication and Prognosis in Angelman's Syndrome

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Angelman syndrome is still not diagnosed as frequently as it occurs. As is often the case with genetic disorders, the cases that tend to be the easiest to diagnose are the ''typical'' cases because they are the most common ones. Therefore, very severe or very mild cases may go unreported because they do not resemble the norm for that diagnosis. Because the manifestations of Angelman syndrome are so severe to begin with, it may be that opportunities to note the most severe cases are not as difficult to recognize as the milder cases. However, to date, very mild cases where development and behavior are close to normal are not abundant, if present at all. There are a few problems with the diagnosis that muddy the waters somewhat. Angelman syndrome is essentially a clinical diagnosis based on a pattern of anomalies including severe developmental impairment, essentially absent speech development, seizures, ataxia, and characteristic craniofacial anomalies along with a number of other physical abnormalities, many of which may be secondary to abnormal muscle tone. It has been found by clinical and molecular genetics that there are a number of DNA alterations that may lead to the development of the Angelman phenotype, including, but not limited to deletion of a segment of the long arm of chromosome 15 from the maternal chromosome, or a phenomenon known as uniparental disomy. The gene that has been implicated in the syndrome is UBE3A, ubiquitin-protein ligase gene although multiple genes are deleted. To complicate matters, there are inconsistencies in how the DNA rearrangements are manifested, such as possible mosaicism (not all of the cells in the individual have the deletion) or abnormal methylation of the region that supervises gene expression. These variations are far too complex to discuss in this response, but suffice it to say that it is likely that those individuals who show less severe manifestations of the syndrome are those individuals who have more rare and less disastrous DNA rearrangements than the typical cases. Because the detection of these rare rearrangements is dependent on very sophisticated molecular genetics technology, it is likely that the clinical presentation of Angelman syndrome is not always correlated to the degree of molecular rearrangement of the DNA. Therefore, it might be easy for a lay person or naive clinician to believe that a child with the clinical diagnosis of Angelman syndrome who is less severely impaired has the same exact condition as the child who is nonverbal. This type of judgment is an example of the need for speech-language pathologists and other behavioral scientists to learn as much as possible about human genetics so our degree of sophistication in discussing prognosis and treatment outcomes is enhanced.

Finally, something needs to be said about ''miracles'' as read online or by parents searching the web. The internet is a wonderful tool for accessing information, but if one surfs the web enough, there is the clear realization that information posted on many, if not most, websites is unedited and not reviewed by experts. Although you can consult web sites like Online Mendelian Inheritance in Man (OMIM) to obtain fabulously up-to-date information on genetic disorders like Angelman syndrome, you can also find recommendations for copper bracelets for arthritis. The bottom line is that the overwhelmingly large majority of patients with Angelman syndrome do not develop speech, and of the few that do, it is rare that they develop more than a few single words. My own experience bears this out, and the professional literature also supports the notion that speech development is absent or very limited in nearly all cases. One case of a mosaic has been reported who had somewhat better speech development, but still severely impaired. The best thing that you can do as clinicians is to do your own online research using professionally edited and reviewed sources, including OMIM, Medline, PubMed, and other appropriate search engines.

References:

Shprintzen, Robert J. (2000). Syndrome Identification for Speech-Language Pathology: An Illustrated PocketGuide. Singular Publishing/Thomson Learning: San Diego, CA.

Dykens, E. M., Hodapp, Robert M, & Finucane, Brenda M. (2000). Genetics and Mental Retardation Syndromes: A New Look at Behavior and Interventions. Paul Brooks Publishing: Baltimore, MD

Robert J. Shprintzen, Ph.D.
Director, Center for Genetic Communicative Disorders
Director, Center for the Diagnosis, Treatment, and Study of Velo-Cardio-Facial Syndrome
Director, Communication Disorder Unit
Professor of Otolaryngology and Communication Science
Professor of Pediatrics
Upstate Medical University
Syracuse, NY


Dr. Shprintzen is currently Director of several programs at University Hospital of Upstate Medical University in Syracuse, NY, including the Communication Disorder Unit, the Center for the Diagnosis, Treatment and Study of Velo-Cardio-Facial Syndrome, and the Center for Genetic Communicative Disorders. He is Professor of Otolaryngology and Communication Sciences and Professor of Pediatrics at Upstate Medical University. Dr. Shprintzen's research career has covered many areas, including clinical genetics, speech physiology, feeding disorders, radiology, fiberoptic endoscopy, cleft palate, and research methodology. He is author or co-author of over 160 peer reviewed papers in more than 25 scholarly journals, and over 20 chapters in scholarly texts. He has published five books including four texts on genetic disorders associated with communication impairment and feeding disorders. He is widely credited for delineating four genetic disorders, several of which bear his name in the medical literature. He is a member of 8 professional societies and has held high office in three. He served as President of the Society of Craniofacial Genetics and also served as Editor for that Society. He was also President of the Society of Ear, Nose, and Throat Advances in Children (SENTAC). He was Editor of The Cleft Palate-Craniofacial Journal from 1988 until 1991. He is an Honorary Fellow of the American Society of Pediatric Otolaryngology. He is a Fellow of the American Speech-Language-Hearing Association. He received the Outstanding Clinical Achievement Award in 1992 from ASHA and the Distinguished Achievement Award in 1992 from the New York State Speech-Language-Hearing Association. Dr. Shprintzen has traveled extensively at the invitation of foreign hospitals and governments in Australia, Brazil, Canada, Denmark, Egypt, England, France, Germany, Israel, Italy, Mexico, The Netherlands, Republic of China, South Africa, Sweden, and Switzerland. He has made over 800 presenta-tions at the annual meetings of more than 40 professional societies and has been an invited speaker or consultant at over 200 hospitals in North America, South America, Europe, Africa, Asia, and Australia. He was the keynote speaker at the Mexican National Congress of Human Genetics in 1999, and in June of 2000, Dr. Shprintzen was a keynote speaker at a meeting sponsored by the World Health Organization in Zurich, Switzerland. He served as a Consultant to the New York City Department of Health and was on the Advisory Board to the Bureau of Families with Special Needs and the Bureau for Handicapped Children for 23 years. In September of 1990, Dr. Shprintzen was one of four expert witnesses to appear before a Congressional Committee to provide testimony on the care of children with craniofacial disorders. In 1995, Dr. Shprintzen was a founding member of The Velo-Cardio-Facial Syndrome Educational Foundation, Inc. and was elected that organization's Executive Director from its inception.