Noonan Syndrome (PTPN11) Sequencing with Reflex to (SOS1) Sequencing
Ordering Recommendation

Acceptable initial test to confirm a clinical diagnosis of Noonan syndrome or LEOPARD syndrome.

Polymerase Chain Reaction/Sequencing
28-35 days
New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory, if possible.
ARUP Consult®
Disease Topics
Specimen Required
Patient Preparation
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B). 
Specimen Preparation
Transport 3 mL whole blood. (Min: 1 mL) 
Storage/Transport Temperature
Unacceptable Conditions
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable 
Reference Interval
Interpretive Data
Background Information for Noonan Syndrome (PTPN11) Sequencing with Reflex to (SOS1) Sequencing:
Characteristics of NS: 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.
Genes tested: PTPN11 and SOS1.
Clinical Sensitivity: Approximately 70 percent.
Methodology: Bidirectional sequencing of the entire PTPN11 coding region and intron-exon boundaries. If no known pathogenic mutations are detected, bidirectional sequencing of the SOS1 coding region and intron-exon boundaries is performed.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations, deep intronic mutations and large deletions/duplications will not be detected. Mutations in genes, other than PTPN11 and SOS1, will not be evaluated.

Compliance Statement C: For human genetic inheritable conditions and mutations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.

Hotline History
CPT Code(s)
Component Test Code*Component Chart NameLOINC
2004190NS REFLEX Specimen
2004192Noonan Syndrome Interpretation
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
  • PTPN11 and SOS1 reflex assay