Prader Willi Syndrome


Prader-Willi syndrome (PWS), occurring in 1/15000 - 1/20000 individuals, is characterised by diminished fetal activity, obesity, muscular hypotonia, developmental delay, short stature, hypogonadotropic hypogonadism, and small hands and feet. The PWS phenotype results from the lack of a paternal contribution at 15q11-q13.

Also known as


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Additional information

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Sending address

Rare & Inherited Disease Laboratory
London North Genomic Laboratory Hub
Great Ormond Street Hospital for Children
Levels 4-6 Barclay House
37 Queen Square

Laboratory service


Sample requirements

1ml EDTA neonates, 5ml EDTA adults

Reference range

Not applicable

Turnaround time

20 days

Disease / group

15q11-q13 (Prader Willi Syndrome)


Upon request

Call in advance?

Prenatals must be arranged in advance, through a Clinical Genetics department if possible.


The Genetics Laboratories provide an extensive range of Cytogenetics and Molecular Genetics diagnostic testing services.

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