RASA1-Related Disorders (RASA1) Sequencing and Deletion/Duplication
2007852
Ordering Recommendation
Preferred molecular test for RASA1-related disorders.
Mnemonic
RASA1 FGA
Methodology
Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification
Performed
Varies
Reported
Within 5 weeks  
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 (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:
75 percent for CM-AVM based on a single study; unknown for other conditions.
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. Large deletions/duplications of exons 16 and 20 may or may not be detected depending on the breakpoint locations. The breakpoints of large deletions/duplications will not be determined.





See Compliance Statement C: www.aruplab.com/CS
Statement C: The performance characteristics of this test were validated by ARUP Laboratories. The U.S. Food and Drug Administration (FDA) has not approved or cleared this test; however, FDA approval or clearance is currently not required for clinical use of this test. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions. ARUP is authorized under Clinical Laboratory Improvement Amendments (CLIA) and by all states to perform high-complexity testing.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
 
Note
 
CPT Code(s)
81479  x2
Components
Component Test Code*Component Chart NameLOINC
2007853RASA1 Seq, Del/Dup Specimen 
2007854RASA1 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