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Test ID FIXMS Hemophilia B, F9 Gene Mutation Analysis, Whole Blood

Useful For

Ascertaining the causative mutation in the F9 gene of patients with congenital hemophilia B (factor IX activity deficiency)


Carrier testing of females in whom the familial F9 genotype is unknown

Method Name

Polymerase Chain Reaction (PCR)/Fluorescent DNA Sequencing

Reporting Name

F9 Gene Mutation Screening, B

Specimen Type

Whole blood

Specimen Required


Preferred: Lavender top (EDTA) or yellow top (ACD)

Acceptable: Sodium citrate

Specimen Volume: 6 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Send specimen in original tube.

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time
Whole blood Ambient (preferred) 7 days
  Frozen  7 days
  Refrigerated  7 days

Reference Values

Not applicable

Day(s) and Time(s) Performed

Monday through Friday

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

81238-F9 (coagulation factor IX) (eg, hemophilia B), full gene sequence

LOINC Code Information

Test ID Test Order Name Order LOINC Value
FIXMS F9 Gene Mutation Screening, B In Process


Result ID Test Result Name Result LOINC Value
23776 F9 Mut Screen Reason for Referral 42349-1
23777 F9 Mutation Screen Method 49549-9
23778 F9 Mutation Screen Result 38896-7
23779 F9 Mutation Screen Interpretation 69049-5
37319 F9 Mutation Screen Specimen Type 31208-2
23781 F9 Mutation Screen Reviewed By 18771-6

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

Testing Algorithm

Maternal cell contamination testing will be performed for all cord blood specimens. A maternal whole blood sample is required to perform this test. 


The following algorithms are available in Special Instructions:

-Hemophilia Carrier Testing Algorithm

-Hemophilia Testing Algorithm

NY State Approved


Reflex Tests

Test ID Reporting Name Available Separately Always Performed
MATCC Maternal Cell Contamination, B Yes No


1. Hemophilia B Patient Information (T518) in Special Instructions is required. Fax the completed form to 507-284-1759.

2. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available in Special Instructions:

-Informed Consent for Genetic Testing (T576)

-Informed Consent for Genetic Testing-Spanish (T826)

3. If not ordering electronically, complete, print, and send a Coagulation Test Request (T753) with the specimen.