ARUP's Laboratory Test Directory

Noonan Syndrome (SOS1) Sequencing : 2004195
[ image for: Patient History for Noonan or Leopard Syndrome Testing]
Patient History for Noonan or Leopard Syndrome Testing
  


Mnemonic: SOS1 FGS

Ordering Recommendation: Diagnostic testing for Noonan syndrome.
Methodology: Polymerase Chain Reaction/Sequencing
Performed: Varies
Reported: Within 28 days
Specimen Required: Collect: Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation: Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature: Refrigerated.

Stability (collection to initiation of testing): Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Interpretive Data: Background Information for Noonan Syndrome (SOS1) Sequencing:
Characteristics: Short stature, developmental delay, dysmorphic facial features, congenital heart disease, broad or webbed neck, superior pectus carinatum and inferior pectus excavatum, low set nipples, cryptorchidism, coagulation and lymphatic disorders.
Incidence: 1 in 1,000 to 1 in 2,500.
Inheritance: Autosomal dominant.
Penetrance: Unknown.
Cause of NS: Pathogenic mutations in PTPN11, SOS1, RAF1, KRAS and other unidentified genes.
Gene tested: SOS1.
Clinical Sensitivity: Approximately 10 percent of NS is due to SOS1 mutations.
Methodology: Bidirectional sequencing of the entire SOS1 coding region and intron-exon boundaries.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Rare diagnostic errors can occur due to primer site mutations. Regulatory region mutations, deep intronic mutations and large deletions/duplications will not be detected. Mutations in genes, other than SOS1, will not be evaluated.



Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.

See Compliance Statement C: www.aruplab.com/CS
CPT Code(s): 81406