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).
Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Transport 3 mL whole blood. (Min: 2 mL)
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
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.
|Component Test Code*||Component Chart Name||LOINC|
|2007853||RASA1 Seq, Del/Dup Specimen|
|2007854||RASA1 Seq, Del/Dup Interp|
- Capillary Malformation-Arteriovenous Malformation Syndrome
- Parkes-Weber Syndrome
- RASA1 sequencing and deletion/duplication assay