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) and FHCC Hematology 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
Forms & Requisitions
- Bloodworks Northwest Eastlake Genomics Laboratory Requisition
Approval Required
Pre-approved for Washington Center for Bleeding Disorders (SEAWBD) and FHCC Hematology. Orders from other locations require LMR approval.
Handling Instructions
Outside Laboratories:
- Refrigerate whole blood while awaiting shipment. Transport with a cold pack.
- Expedite transport; samples must be received by Bloodworks within 72 hours of collection. Allow for an additional day of transport from UW-MT to Bloodworks Northwest.
- 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): Refrigerated (preferred): 72 hours; Ambient: 48 hours; Frozen: Approved for WA Center for Bleeding Disorders (-20°C or -70/80°C). Avoid thawing/re-freezing.
Quantity
requested: 10 mL EDTA whole blood
minimum: 6 mL EDTA whole blood
Processing
Result-at-Entry:
- RHEMBS (Sample Type): <Enter appropriate specimen type code.>
- Specimen Type Code(s):
- WB (Whole Blood)
- CULAMN (Cultured Amniocytes)
- Specimen Type Code(s):
Processing:
- Whole blood received at ambient temperature should be refrigerated. Ambient/refrigerated samples must be received at Bloodworks within 72 hours.*
- Whole blood received frozen should be stored frozen and transported on dry ice. WA Center for Bleeding Disorders has pre-arranged with BWNW to send samples frozen for extended specimen stability.
- 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.
- Store cultured amniocytes at ambient temperature and ship same-day.
Sendouts:
- Order Bloodworks NW Test: 3250-10.
- For orders not placed in Epic or via the ISEAWBD interface, a separate Bloodworks Northwest Eastlake Genomics requisition is required. Otherwise, send with a copy of the Epic requisition or ISEAWBD eREQ.
- Affix CAST "Billing" and "Results To" labels to the outgoing requisition.
- 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.
- Send blood orders as received with the UW DLMP or Delivery Express courier directly to the Bloodworks NW Eastlake location (do not route through BWNW Central Lab).
- Cultured amniocytes must be sent same-day to the Bloodworks Central Genomics Lab (921 Terry Ave, Seattle WA 98104).
- 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.*
Stability (Whole Blood): Refrigerated (preferred): 72 hours; Ambient: 48 hours; Frozen: Approved for WA Center for Bleeding Disorders (-20°C or -70/80°C). Avoid thawing/re-freezing.
Stability (Cultured Amniocytes): Ambient.
*Contact the Bloodworks NW Eastlake Genomics Lab at 206-568-2184 for sample acceptability questions prior to cancelling orders outside of the stated stability window.
Performance
LIS Dept Code
Sendouts (SO)
Performing Location(s)
| Sendout |
Bloodworks Northwest Eastlake Genomics Laboratory
1551 Eastlake Ave E |
|---|
Frequency
Turn around Time: 5-10 business days from sample receipt at Bloodworks Eastlake Genomics.
Available STAT?
No