Prader-Willi Syndrome FISH Analysis

Related Gene(s): MAGEL2, MKRN3, OCA2, snoRNAs, SNRPN

Prader-Willi syndrome (chromosome location 15q11.2q13) FISH (fluorescence in situ hybridization) is offered for diagnosis of individuals with clinical features of Prader-Willi syndrome, including intellectual disability, hypotonia, hypogonadism, food obsession, and behavior problems. The detection rate of FISH analysis for this disorder is approximately 70%.

Specimen Requirements


  • Amniotic fluid: Minimum total specimen size 15 mL
  • Chorionic villi: Minimum total specimen size 4 mg


  • Whole blood: Minimum 5-10 mL in sodium heparin tube (green top)

Ordering Information


  • Ship at room temperature

Turnaround Time

  • Prenatal: 5-7 days
  • Postnatal: 7-10 days

Related Tests


Prenatal Test Requisition with Natera NIPT
Prenatal Test Requisition with Sequenom NIPT
General Test Requisition
Chromosomal Microarray Information Sheet