Detect pathogenic EPHB4 variants. Confirm diagnosis in individuals with findings suggestive of capillary malformation-arteriovenous malformation syndrome type 2.
Polymerase Chain Reaction/Sequencing
Within 2 weeks
Lavender (EDTA), Pink (K2EDTA), or Yellow (ACD).
Transport 3 mL whole blood. (Min: 1 mL)
Ambient: 1 week; Refrigerated: 1 month; Frozen: 6 months
Background Information for Capillary Malformation-Arteriovenous Malformation 2 (EPHB4) Sequencing:
Characteristics of Capillary Malformation-Arteriovenous Malformation (CM-AVM): 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, or central nervous system can cause life-threatening complications such as bleeding, congestive heart failure, or neurological consequences. Capillary malformation-arteriovenous malformation syndrome type 1 (CM-AVM1) is caused by RASA1 pathogenic variants; capillary malformation-arteriovenous malformation syndrome type 2 (CM-AVM2) is caused by EPHB4 pathogenic variants.
Incidence: Estimated at 1 in 20,000 for CM-AVM1 and 1 in 12,000 for CM-AVM2.
Inheritance: Autosomal dominant.
Penetrance: 90-95 percent.
Cause: Pathogenic EPHB4 or RASA1 gene variants.
Gene Tested: EPHB4 only.
Clinical Sensitivity: Not well established, at least 15 percent.
Methodology: Bidirectional sequencing of all coding regions and intron-exon boundaries of the EPHB4 gene.
Analytical Specificity and Sensitivity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region variants, deep intronic variants, and large deletions/duplications will not be detected. Variants in genes other than EPHB4 are not detected.
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|
|3001130||CMAVM EPHB4 FGS Specimen|
|3001131||CMAVM EPHB4 FGS Interpretation|
- CM-AVM2, Capillary Malformation-Arteriovenous Malformation2