von Willebrand Disease, Type 2M (VWF) Sequencing
2005490
Ordering Recommendation
Molecular testing  to confirm a phenotypic diagnosis of von Willebrand disease type 2M.
Mnemonic
VWF2M SEQ
Methodology
Polymerase Chain Reaction/Sequencing
Performed
Varies
Reported
Within 21 days  
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: 1 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 von Willebrand Disease, Type 2M (VWF) Sequencing:
Characteristics
: Mucocutaneous bleeding after brushing or flossing teeth, unexplained bruising, prolonged repeated nosebleeds, menorrhagia, and prolonged bleeding following childbirth, trauma or surgery.
Incidence
: Approximately 1 in 100 to 1 in 1000 individuals.
Inheritance:
Autosomal dominant for type 2M.
Penetrance:
Dominant mutations are incompletely penetrant when VWF:Ag and VWF:RCo levels are 25-50 IU/dL. Full penetrance is expected when VWF:Ag and VWF:RCo levels are less than 25 IU/dL.
Cause
: Pathogenic VWF mutations in exons 28, 30, and 31.
Clinical Sensitivity
: 80 percent for vWD types 2A, 2B, and 2M; unknown for other vWD subtypes.
Methodology:
Bidirectional sequencing of VWF exons 28, 30, 31 and its 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 deletion/duplications will not be detected. Mutations lying outside of VWF exons 28, 30, and 31 will not be evaluated.





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)
81404
Components
Component Test Code*Component Chart Name
2005491vWD Type 2M (VWF) Sequencing Specimen
2005492vWD Type 2M (VWF) Sequencing 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
  • VWD type 2M sequencing assay
  • VWF2M Sequencing