Hemophilia B DNA Evaluation (Sendout)
General Information
Lab Name
Hemophilia B DNA Evaluation (Sendout)
Lab Code
RDHEMB
Epic Name
Hemophilia B DNA Evaluation (Sendout)
External Test Id
3250-10
Description
Test Information: Analysis of the Factor IX gene (Hemophilia B) is performed by direct sequence analysis of exons 1 – 8 and one common recurrent 3′ ut region genotype. The Genomics Testing Laboratory has had a high level of success in locating the mutation within these areas (Weinmann et al, BJ Haematol 100: 58, 1998).
If the specific mutation cannot be identified, intragenic linkage is often useful to trace the affected allele through the family tree by following 4 polymorphic sites. Linkage studies also help identify the de novo origin of mutations in families with an isolated occurrence (eg maternal grandparents). Intragenic linkage may be useful in 80-90% of families where key family members (patient and both parents of potential carrier) are available.
Additional Test Information: Sequencing is performed for exons 1-8 and the 3′ ut region. 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.
Ordering Requirements:
- Orders from Washington Center for Bleeding Disorders (SEAWBD), FHCC Hematology, and UW Medicine Prenatal Genetics are pre-approved. Orders from other locations require Laboratory Medicine Resident approval.
- For orders not submitted via Epic or ISEAWBD interface, providers must complete a Bloodworks Eastlake Genomics Lab Requisition
References
- Factor IX Gene (F9) Variant Database
- CDC Hemophilia Mutation Project: CHAMP & CHBMP
- Bloodworks Northwest Ordering Information: Bleeding Disorders
Synonyms
3250-10, F9 Genotyping, HemB Genotyping, Hemophilia B
Components
| Code | Name |
|---|---|
| RHEMBS | Hemophilia B DNA Evaluation Sample Type |
| RHEMBR | Hemophilia B DNA Evaluation Result |
| RHEMBL | Hemophilia B DNA Evaluation Performing Lab |
Interpretation
Method
Polymerase Chain Reaction (PCR) Based
Reference Range
See individual components
Ref. Range Notes
See report.
Ordering & Collection
Specimen Type
Collection
Whole Blood: 10 mL LAVENDER TOP EDTA tube
Cultured Amniocytes: Two T-25 flasks of cells cultured to confluency.
- Amniotic fluid is not accepted.
- An EDTA whole blood sample from the mother of the fetus must accompany cultured amniocyte orders.
Extracted DNA: >10 ug extracted DNA at a concentration of >25ng/ul
Collection Timing:
- Collect any time Monday through Thursday.
- Samples collected on a Friday must be timed appropriately to ensure delivery at Bloodworks Eastlake Lab by the 1 p.m. cutoff.
Samples sent on Fridays must be received at Bloodworks Northwest Genomics Lab by 1 p.m.
Forms & Requisitions
- Bloodworks Northwest Eastlake Genomics Laboratory Requisition
Approval Required
Pre-approved for Washington Center for Bleeding Disorders (SEAWBD), FHCC Hematology, and UW Medicine Prenatal Genetics. Orders from other locations require LMR approval.
Handling Instructions
Outside Laboratories:
- Store and transport whole blood at ambient temperature.
- Expedite transport; samples must be received by Bloodworks NW within 72 hours of collection and before 1 p.m. on Fridays. Allow for one day of transport from UW-MT to Bloodworks Northwest.
- Unless the cells are cultured at UW-MT Cytogenetics and Genomics Lab, clients should arrange to send cultured amniocyte samples directly to Bloodworks NW due to the short stability window.
- Submit a completed Bloodworks Northwest Eastlake Genomics Requisition along with the DLMP Requisition.* Leave the billing section blank to be completed by Sendouts staff.
- *Use client-specific requisition when available. To obtain a client-specific requisition, contact Client Support Services via email at: commserv@uw.edu.
- WA Center for Bleeding Disorders only: A separate Bloodworks NW requisition is not required for orders submitted via interface.
Stability (Whole Blood): Ambient (preferred): 72 hours; Refrigerated: 72 hours; Frozen: -20°C or -70/80°C. Avoid thawing/re-freezing.
- Frozen EDTA tube(s) are accepted if samples are frozen the day of the blood draw, never thawed, and are shipped and received on dry ice. Contact Eastlake Bleeding Disorders at (206) 568-2184 with questions about sample acceptability.
Quantity
requested: 10 mL EDTA whole blood
minimum: 3 mL EDTA whole blood
Processing
Result-at-Entry:
- RHEMBS (Hemophilia B DNA Evaluation Sample Type): <Specimen type will file automatically for orders placed in Epic. For others, enter the appropriate specimen type code.>
Specimen Type Codes:
| ETC | Translation |
| WB | Whole Blood |
| CULAMN | Cultured Amniocytes |
| DNAEXT | Extracted DNA |
Processing:
- Maintain whole blood and cultured amniocyte samples at ambient temperature.
- Whole blood received frozen should be stored frozen.
- If sample is collected on a Friday, notify Sendouts immediately upon sample receipt to ensure delivery to Bloodworks NW by the 1 p.m. cutoff.
Sendouts:
- Order Bloodworks NW Test: 3250-10
- Submit a copy of the ISEAWBD eREQ or Epic requisition with the sample (ensure that all pages are printed to accommodate the order questions). For orders not placed in Epic or via the ISEAWBD interface, a separate Bloodworks Northwest Eastlake Genomics requisition is required.
- Package sample(s) with the associated requisition in a biohazard bag (one patient per bag). Orders received with multiple
patient samples/requisitions in the same biozard bag will be rejected by Bloodworks NW. - Blood:
- Send blood orders as received with the UW DLMP or Delivery Express courier directly to the Bloodworks NW Eastlake location.
- Transport whole blood at ambient temperature. Whole blood received frozen should be stored frozen and transported on dry ice.
- Samples may be sent Monday through Friday only. If sent on a Friday, samples must be in lab at the Eastlake location by 1 p.m.
- Ambient or refrigerated whole blood samples must arrive at Bloodworks within 72 hours of collection.
- Cultured amniocytes:
- Send cultured amniocytes same-day to the Bloodworks Central Genomics Lab (921 Terry Ave, Seattle WA 98104).
- Cultured amniocytes must arrive at Central Genomics within 48 hours of collection and by 1 p.m. on Fridays.
Stability (Whole Blood): Ambient (preferred): 72 hours; Refrigerated: 72 hours; Frozen: -20°C or -70/80°C. Avoid thawing/re-freezing.
- Frozen EDTA tube(s) are accepted if samples are frozen the day of the blood draw, never thawed, and are shipped and received on dry ice. Contact Eastlake Bleeding Disorders at (206) 568-2184 with questions about sample acceptability.
Stability (Cultured Amniocytes): Samples must arrive within 48 hours to the Central Genomics location (amniocytes should not be sent to the Eastlake laboratory).
Performance
LIS Dept Code
Sendouts (SO)
Performing Location(s)
| Sendout |
Bloodworks Northwest Eastlake Genomics Laboratory
206-568-2184 1551 Eastlake Ave E |
Also known as: Bloodworks Northwest Bleeding Disorders Laboratory |
|---|
Frequency
Turn around Time: 5-10 business days from sample receipt at Bloodworks Eastlake Genomics.
Available STAT?
No