Ordering Recommendation

Acceptable test to confirm diagnosis or determine carrier status for F9 gene variants.

Mnemonic
F9 FGS
Methodology

Polymerase Chain Reaction/Sequencing

Performed

Varies

Reported

14-21 days

New York DOH Approval Status
This test is New York DOH approved.
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
Interpretive Data

Background Information for Hemophilia B (F9) Sequencing:
Characteristics:
Severe deficiency of factor IX clotting activity is associated with spontaneous joint or deep tissue bleeding.  Moderate or mild deficiency is associated with prolonged bleeding after tooth extractions, surgery, or injuries and recurrent or delayed wound healing.
Incidence: 1 in 25,000 males worldwide.
Penetrance: 100 percent in males and 10 percent in females.
Inheritance: X-linked recessive.
Cause: Deleterious F9 gene mutations.
Clinical Sensitivity: 97 percent.
Methodology: Bidirectional sequencing of the entire F9 coding region and intron-exon boundaries and proximal promoter.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Deep intronic mutations and gene duplications will not be detected in patients of either sex; large deletions will not be detected in females.

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.

Note
Hotline History
N/A
Components
Component Test Code* Component Chart Name LOINC
2001580 Hemophilia B Interpretation
2001581 F9 FGS Specimen
* 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
  • Christmas Disease
  • F9
  • F9 sequencing
  • Factor IX
Hemophilia B (F9) Sequencing