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GTR Home > Tests > MS-MLPA for Angelman/Prader Willi syndrome


Test name


MS-MLPA for Angelman/Prader Willi syndrome

Purpose of the test


This is a clinical test intended for Help: Diagnosis, Screening, Monitoring, Pre-symptomatic, Mutation Confirmation



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Click Indication tab for more information.

How to order


All samples should be shipped via overnight delivery at room temperature. No weekend or holiday deliveries. Label each specimen with the patient’s name, date of birth and date sample collected. Send specimens with complete requisition and consent form, otherwise, specimen processing may be delayed.
Order URL Help: http://dnatesting.uchicago.edu/submitting-sample

Specimen source

Isolated DNA
Fetal blood
Chorionic villi
Cord blood
Product of conception (POC)
Peripheral (whole) blood
Amniotic fluid
Cell culture
Buccal swab
Frozen tissue


Molecular Genetics
MMethylation analysis
Methylation-specific PCR

Summary of what is tested

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Click Methodology tab for more information.

Clinical utility


Not provided

Clinical validity


Approximately 70% of individuals with PWS have a de novo deletion of 15q11-q13 on the paternally contributed chromosome, corresponding to a less than 1% recurrence risk [2]. Approximately 25% of PWS is due to maternal UPD15, corresponding to a less than 1% recurrence risk [2]. 2-5% of patients have an imprinting center (IC) abnormality of which 10-40% are deletions of the IC region. A recurrence risk of up to 50% applies to the IC deletion group and a low recurrence risk of less than 1% applies to the remainder of the IC abnormality group [2]. Less than 1% of PWS is due to a paternal chromosome 15 translocation, which may result in a recurrence risk of up to 25% [2].

  • Population prevalence and estimated birth incidence and mortality rate for people with Prader-Willi syndrome in one UK Health Region. - PubMed ID: 11732491

Test services

  • Clinical Testing/Confirmation of Mutations Identified Previously
  • Confirmation of research findings
  • Custom Prenatal Testing

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