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.



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
Note
CPT Code(s)
81479 x2
Components
Component Test Code*Component Chart Name
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.
Cross References
  • Capillary Malformation-Arteriovenous Malformation Syndrome
  • Parkes-Weber Syndrome
  • RASA1 sequencing and deletion/duplication assay