Test Catalog

Test ID: F12NG    
F12 Gene, Next-Generation Sequencing, Varies

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Factor XII deficiency:

Special coagulation testing for factor XII (F_12 / Coagulation Factor XII Activity Assay, Plasma) should be performed prior to any genetic testing.


Genetic testing for factor XII deficiency may be considered if:

-Factor XII activity is reduced (less than 55% of normal)

-Acquired causes of factor XII have been excluded


Hereditary angioedema type III (FXII-HAE):

An international consortium has established a testing and diagnostic algorithm for the identification of hereditary angioedema (HAE) type III.(1)

Specimen Type Describes the specimen type validated for testing


Ordering Guidance

Genetic testing for factor XII deficiency typically has little clinical utility. Caution in ordering is advised.


For hereditary angioedema type III, genetic testing should only be considered when there is a documented family history of angioedema that does not respond to chronic, high-dose antihistamine therapy, normal complement studies, normal C1 inhibitor level and function, and no exposure to medications that could cause angioedema, such as angiotensin-converting enzyme (ACE) inhibitors or nonsteroidal anti-inflammatory drugs.

Shipping Instructions

Ambient and refrigerated specimens must arrive within 7 days (168 hours of draw), and frozen specimens must arrive within 14 days (336 hours of draw).

Collect and package specimen as close to shipping time as possible.

Necessary Information

Rare Coagulation Disorder Patient Information is required, see Special Instructions. Testing may proceed without the patient information, however, the information aids in providing a more thorough interpretation. Ordering providers are strongly encouraged to fill out the form and send with the specimen.

Specimen Required Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Submit only 1 of the following specimens:


Specimen Type: Peripheral blood


Preferred: Lavender top (EDTA)

Acceptable: Yellow top (ACD) or green top (sodium citrate)

Specimen Volume: 3 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Send specimen in original tube.

Specimen Stability: Ambient (preferred)/Refrigerated/Frozen


Specimen Type: Extracted DNA

Container/Tube: 1.5- to 2-mL tube

Specimen Volume: Entire specimen

Collection Instructions:

1. Label specimen as extracted DNA and source of specimen.

2. Provide indication of volume and concentration of the DNA.

Specimen Stability: Frozen (preferred)/Refrigerated/Ambient

Special Instructions Library of PDFs including pertinent information and forms related to the test


1. Rare Coagulation Disorder Patient Information (T824) is required, see Special Instructions. 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.

Specimen Minimum Volume Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

Blood: 1 mL
Extracted DNA: 100 mcL at 50 ng/mcL concentration

Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis OK
Gross lipemia OK

Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen TypeTemperatureTimeSpecial Container
VariesAmbient (preferred)7 days
 Frozen 14 days
 Refrigerated 7 days