DNA von Willebrand Disease Type 2A/2B/2M

Also Known as (Alias) VWD genotyping
Method polymerase chain reaction (PCR) based
Test Information Von Willebrand Disease (VWD) is one of the most common inherited bleeding disorders. This disorder is divided into three types, Type 1, Type 2 and Type 3. All types of this condition cause prolonged bleeding episodes of varying severity; Type 1 is the mildest of the three types and Type 3 is the most severe. Type 2 is intermediate in severity and is further divided into four subtypes. Type 2A VWD is the most common form of Type 2, accounting for 70% of the Type 2 diagnosis

Mutations in the von Willebrand Factor (VWF) gene cause VWD. This disease can have different inheritance patterns. Type 1 and Type 2 (2A, 2B, and 2M) are inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. Type 3 and Type 2N are inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations.

NHIBI Guidelines
VWF Mutation Database
Additional Test Information The Von Willebrand Factor Screen sequences up to 9 exons for mutations depending on the type. Confirmation is performed one of two ways. If the mutation creates/removes a restriction enzyme digestion site, the testing will be performed by RFLP. If a restriction enzyme digestion site is not present, testing will be done by sequencing the exon in which the mutation is located
Sample Requirements EDTA (lavender top)
Requested Volume 5-10cc EDTA (lavender top) tube

Analysis of amniocytes can be performed on cultured amniocytes. Two T-25 flasks of cells cultured to confluency will be accepted. Bloodworks Northwest does not have facilities to culture amniocytes.  Bloodworks Northwest does not have facilities to culture amniocytes.
Shipping Information Whole blood shipped at 4oC or ambient temperature is acceptable and should arrive in the lab within 48 hours.

Send samples to:
Bloodworks Northwest
Eastlake SDL
1551 Eastlake Ave E.
Seattle, WA 98102

For additional information please see Ordering Information
Requisition Form Request for Testing Hemostasis Reference Laboratory
Transaction Code 3250-08
CPT Codes 81403
Turn around Time (analytic time) 5-10 business days
Report/Results Fax number required to receive report