Acceptable 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).
- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
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 the entire RASA1 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
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|2002731||RASA1 FGS Specimen|
|2002732||RASA1-Related Disorders Sequencing|
- Capillary Malformation-Arteriovenous Malformation Syndrome
- Parkes-Weber Syndrome
- RASA1 sequencing assay