Hemophilia A (F8) Sequencing
2001747
 
Ordering Recommendation
Order to sequence the F8 gene to identify the causal mutation in individuals with established mild to moderate hemophilia A. For severe hemophilia A, Hemophilia A (F8) 2 Inversions with Reflex to Sequencing and Reflex to Deletion/Duplication (2001614) is recommended.
Mnemonic
F8 FGS
Methodology
Polymerase Chain Reaction/Sequencing
Performed
Varies
Reported
Within 28 days
New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory.
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 A (F8) Sequencing:
Characteristics:
Severe deficiency of factor VIII clotting activity leading to spontaneous joint or deep muscle bleeding. Moderate to mild deficiency is associated with prolonged bleeding after tooth extractions, surgery, or injuries and recurrent or delayed wound healing.
Incidence:
1 in 4,000-5,000 live male births worldwide, rare in females.
Inheritance:
X-linked recessive. Of simplex cases, 85 percent of mothers are carriers and 10-15 percent of boys have a de novo mutation.
Penetrance:
100 percent in males and 10 percent in females.
Cause:
Deleterious F8 gene mutations.
Clinical Sensitivity:
98 percent of mutations causing mild to moderate hemophilia A and 43 percent of severe hemophilia A mutations are detected by sequencing.
Methodology:
Bidirectional sequencing of the entire F8 coding region and 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 gene duplications will not be detected in patients of either sex; large deletions will not be detected in females.



Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.

See Compliance Statement C: www.aruplab.com/CS
Note
CPT Code(s)
81407
Components
Component Test Code*Component Chart Name
2001749Hemophilia A (F8) Sequencing Interp
2001750F8 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, contact interface support at interface.support@aruplab.com.
Cross References
  • F8 (Hemophilia A (F8) Sequencing)
  • Factor VIII (Hemophilia A (F8) Sequencing)