Ordering Recommendation

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

Mnemonic
PTPN11 FGS
Methodology

Polymerase Chain Reaction/Sequencing

Performed

Varies

Reported

14-21 days

New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory, if possible.
Specimen Required
Patient Preparation
Collect

Lavender (K2EDTA), Pink (K2EDTA), or Yellow (ACD Solution A or B).

Specimen Preparation

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

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions
Remarks
Stability

Ambient: 1 week; Refrigerated: 1 month; Frozen: 6 months

Reference Interval
Interpretive Data

Background Information for Noonan Syndrome (PTPN11) Sequencing:
Characteristics of Noonan Syndrome (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.
Characteristics of LEOPARD syndrome:
Lentigines, ECG abnormalities, ocular hypertelorism, pulmonary stenosis, abnormal genitalia, retardation of growth, and deafness.
Incidence:
1 in 1000 to 1 in 2500 for NS; rare for LEOPARD syndrome.
Inheritance:
Autosomal dominant.
Penetrance:
Unknown.
Cause of NS:
Deleterious mutations in PTPN11, SOS1, RAF1, KRAS and other unidentified genes.
Cause of LEOPARD syndrome:
Mutations in PTPN11 exons 7 and 12 as well as other unidentified genes.
Gene tested:
 PTPN11.
Clinical Sensitivity:
50 percent of NS is due to PTPN11 mutations; unknown for LEOPARD syndrome.
Methodology:
Bidirectional sequencing of the entire PTPN11 coding region and intron-exon boundaries.
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, will not be detected. This assay is not designed to detect somatic variants associated with malignancy. Interpretation of this test result may be impacted if the patient has had an allogeneic stem cell transplantation.

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.

Note
Hotline History
N/A
CPT Codes

81406

Components
Component Test Code* Component Chart Name LOINC
0051806 Noonan Syndrome (PTPN11) Sequencing
2001373 PTPN11 FGS Specimen
* 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.
Aliases
  • Leopard Syndrome
  • PTPN11 sequencing assay
  • PTPN11, Full Gene Sequence, Blood
Noonan Syndrome (PTPN11) Sequencing