Ordering Recommendation

Preferred DNA test for RASA1-related disorders. Confirm diagnosis in individuals with findings suggestive of capillary malformation-arteriovenous malformation (CM-AVM) syndrome or Parkes Weber syndrome (PKWS).

Mnemonic
RASA1 FGA
Methodology

Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification

Performed

Varies

Reported

28-35 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation

Transport 3 mL whole blood. (Min: 2 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions
Remarks
Stability

Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable

Reference Interval

By report

Interpretive Data

Background Information for RASA1-Related Disorders (RASA1) Sequencing and Deletion/Duplication:
Characteristics:
Multifocal, randomly distributed, capillary malformations (CM) that may be associated with a fast-flow lesion (arteriovenous malformations [AVM] or arteriovenous fistula). Fast-flow lesions in the skin, muscle, bone, internal organs or brain can cause life-threatening complications such as bleeding, congestive heart failure, or neurological consequences. Capillary malformation-arteriovenous malformation syndrome (CM-AVM) and Parkes-Weber syndrome may be caused by RASA1 mutations.
Incidence:
Estimated at 1 in 100,000.
Inheritance:
Autosomal dominant; approximately one-third are de novo.
Penetrance: 90-95 percent.
Cause:
Pathogenic RASA1 gene mutations.
Clinical Sensitivity:
Approximately 70 percent.
Methodology:
Bidirectional sequencing of all coding regions and intron-exon boundaries of the RASA1 gene; Multiplex Ligation-dependent Probe Amplification (MLPA) to detect large RASA1 deletions/duplications.
Analytical Specificity and Sensitivity:
99 percent.
Limitations
: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations and deep intronic mutations will not be detected. The breakpoints of large deletions/duplications will not be determined.

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

81479

Components
Component Test Code* Component Chart Name LOINC
2007853 RASA1 Seq, Del/Dup Specimen
2007854 RASA1 Seq, Del/Dup Interp
* 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
  • Capillary Malformation-Arteriovenous Malformation Syndrome
  • Parkes-Weber Syndrome
  • RASA1 sequencing and deletion/duplication assay
RASA1-Related Disorders (RASA1) Sequencing and Deletion/Duplication