Expertisecentrum Phelan-McDermid syndroom
Phelan-McDermid syndroom poli is onderdeel van het Expertisecentrum Uniek voor zeldzame genetische oorzaken van ontwikkelingsachterstand (neurodevelopmental disorders)
This page is only available in English. For information in Dutch please go to Phelan-McDermid syndroom poli.
What is Phelan McDermid syndrome?
Phelan-McDermid syndrome is a rare, congenital disorder. Characteristics of this disorder include behavioral problems and developmental delays, especially in the areas of speech, language, and language comprehension. Another name is 22q13.3 deletion syndrome.
What is the cause of Phelan-McDermid syndrome?
Phelan McDermid syndrome is usually caused by a part of chromosome 22 missing. A missing piece of chromosome is called a deletion. Another name is therefore the 22q13.3 deletion syndrome.
The part of chromosome 22 that is missing contains the SHANK3 gene. Due to the deletion, there is a deficiency of the SHANK3 protein. This protein is important for brain development and plays a role in signal transmission between brain cells. When there is a deficiency of SHANK3 protein, the characteristics of Phelan-McDermid syndrome arise.
Some people with this syndrome do not have a deletion. The SHANK3 gene is still present, but there is a change in the letter code (mutation) of the SHANK3 gene itself. Because of this change in the gene, too little SHANK3 protein is produced, which causes Phelan-McDermid syndrome.
In some patients, the 22q13.3 deletion is due to a ring chromosome 22. This means that chromosome 22 has taken on a ring shape, so that the piece 22q13.3 is missing. This is important to investigate. Because of the ring shape, there is a greater chance of benign tumours of nerve tissue. This can cause hearing loss, for example.
What are the main features of Phelan-McDermid syndrome?
The main characteristics that occur in a large proportion of patients with Phelan-McDermid syndrome are:
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Developmental delays, especially speech and language comprehension, but also severe learning difficulties
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Behavioural problems such as ADHD and autism
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Sleep problems
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Epilepsy
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Low muscle tone (hypotonia)
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Congenital anomalies, including heart and kidney defects
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Less or altered sensitivity to pain
People with Phelan-McDermid syndrome may also have other characteristics. Not everyone has the same features.
What is the Phelan-McDermid syndrome centre of expertise?
The clinic aims to coordinate the care for children and adults with Phelan-McDermid syndrome and functions as a centre of expertise. All patients are seen by a team of specialists. The medical specialists involved in the Phelan-McDermid centre can be found at the UMCG website.
At the beginning of 2024, the clinic has records on over 100 Phelan-McDermid syndrome patients, most of whom are still being followed and seen at intervals of two years. This has led to an enormous amount of practical experience with the syndrome. The clinic facilitates scientific research on Phelan-McDermid syndrome. For more information please see our other webpages on research in Phelan-McDermid syndrome.
Other Phelan-McDermid syndrome clinics
Phelan-McDermid syndrome clinics can also be found in Germany (Ulm, S. Jesse), Belgium (Leuven, G. van Buggenhout), France (Paris, A. Maruani), Spain (Madrid, J. Nevado), Italy.
For more information see: https://ern-ithaca.eu/documentation/phelan-mcdermid-guideline/
Useful links
For information in Dutch see UMCG website
Information in English:
Contact
22q13@umcg.nl
Contact person: Drs. C. Frantzen, MD, clinical geneticist and coordinator of the centre of expertise for Phelan-McDermid syndrome
| Laatst gewijzigd: | 08 mei 2024 14:01 |