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HelpTest Code GNF13 Factor XIII Deficiency, F13A1 and F13B Genes, Next-Generation Sequencing, Varies
Ordering Guidance
Special coagulation testing for factor XIII (FXIII) activity should be performed prior to any genetic testing. For assessment of FXIII activity, order ALBLD / Bleeding Diathesis Profile, Limited, Plasma, which includes the factor XIII screening assay.
Genetic testing should only be considered if clinical and family history, initial coagulation screens, or initial activity tests indicate a diagnosis of FXIII deficiency (see Testing Algorithm).
If genetic testing for hereditary bleeding disorders using a larger panel is desired, both a 6-gene focused bleeding panel and a 25-gene comprehensive bleeding panel are available. For more information see GNBLF / Bleeding Disorders, Focused Gene Panel, Next-Generation Sequencing, Varies or GNBLC / Bleeding Disorders, Comprehensive Gene Panel, Next-Generation Sequencing, Varies.
Testing for the F13A1 and F13B genes as part of a customized panel is available. For more information see CGPH/ Custom Gene Panel, Hereditary, Next-Generation Sequencing, Varies.
Targeted testing for familial variants (also called site-specific or known mutations testing) is available for the F13A1 and F13B genes. See FMTT / Familial Variant, Targeted Testing, Varies. To obtain more information about this testing option, call 800-533-1710.
Additional Testing Requirements
All prenatal specimens must be accompanied by a maternal blood specimen; order MATCC / Maternal Cell Contamination, Molecular Analysis, Varies on the maternal specimen as this must be a different order number than the prenatal specimen.
Shipping Instructions
Specimen preferred to arrive within 96 hours of collection.
Necessary Information
Rare Coagulation Disorder Patient Information is required. 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
Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. For instructions for testing patients who have received a bone marrow transplant, call 800-533-1710.
Submit only 1 of the following specimens:
Specimen Type: Whole blood
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Yellow top (ACD)
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
Specimen Stability Information: Ambient (preferred) 4 days/Refrigerated
Prenatal Specimens
Due to its complexity, consultation with the laboratory is required for all prenatal testing; call 800-533-1710 to speak to a genetic counselor.
Specimen Type: Amniotic fluid
Container/Tube: Amniotic fluid container
Specimen Volume: 20 mL
Specimen Stability Information: Refrigerated (preferred)/Ambient
Additional information:
1. A separate culture charge will be assessed under CULAF / Culture for Genetic Testing, Amniotic Fluid.
2. All prenatal specimens must be accompanied by a maternal blood specimen; order MATCC / Maternal Cell Contamination, Molecular Analysis, Varies on the maternal specimen.
Specimen Type: Chorionic villi
Container/Tube: 15-mL tube containing 15 mL of transport media
Specimen Volume: 20 mg
Specimen Stability Information: Refrigerated
Additional Information:
1. A separate culture charge will be assessed under CULFB / Fibroblast Culture for Biochemical or Molecular Testing.
2. All prenatal specimens must be accompanied by a maternal blood specimen; order MATCC / Maternal Cell Contamination, Molecular Analysis, Varies on the maternal specimen.
Acceptable:
Specimen Type: Confluent cultured cells
Container/Tube: T-25 flask
Specimen Volume: 2 Flasks
Collection Instructions: Submit confluent cultured cells from another laboratory.
Specimen Stability Information: Ambient (preferred)/Refrigerated
Additional Information:
All prenatal specimens must be accompanied by a maternal blood specimen; order MATCC / Maternal Cell Contamination, Molecular Analysis, Varies on the maternal specimen.
Forms
1. Rare Coagulation Disorder Patient Information (T824) is required
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:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing (Spanish) (T826)
3. If not ordering electronically, complete, print, and send an Coagulation Test Request (T753) with the specimen.
Useful For
Evaluating factor XIII deficiency (FXIIID) in patients with a personal or family history suggestive of FXIIID
Confirming an FXIIID diagnosis with the identification of known or suspected disease-causing alterations in the F13A1 or F13B genes
Determining the disease-causing alterations within the F13A1 or F13B genes to delineate the underlying molecular defect in a patient with a laboratory diagnosis of FXIIID
Identifying the causative alterations for genetic counseling purposes
Prognosis and risk assessment based on the genotype-phenotype correlations
Carrier testing for close family members of an individual with a diagnosis of FXIIID
Genetics Test Information
This test utilizes next-generation sequencing to detect single nucleotide and copy number variants in the F13A1 and F13B genes associated with factor XIII deficiency (FXIIID), a rare bleeding disorder. See Method Description for additional details.
Identification of a disease-causing variant may assist with diagnosis, prognosis, clinical management, recurrence risk assessment, familial screening, and genetic counseling for FXIIID.
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| CULFB | Fibroblast Culture for Genetic Test | Yes | No |
| CULAF | Amniotic Fluid Culture/Genetic Test | Yes | No |
| MATCC | Maternal Cell Contamination, B | Yes | No |
Testing Algorithm
The clinical workup for factor FXIII deficiency (FXIIID) should begin with special coagulation testing for factor XIII activity.
A standard testing algorithm for FXIIID has been developed by the Scientific and Standardization Committee of the International Society for Thrombosis and Haemostasis.(1)
Genetic testing for FXIIID is indicated if:
-The clot solubility test, a screening test for possible factor XIII deficiency, is abnormal or FXIII antigen or activity is decreased
-Acquired causes of FXIIID have been excluded (eg, leukemia, liver disease, Henoch-Schonlein purpura, inflammatory bowel diseases, disseminated intravascular coagulation, pulmonary embolism, stroke, and sepsis, exposure to valproate)
Note: Factor XIII may occur spontaneously in older adults.
For prenatal specimens only:
-If amniotic fluid (nonconfluent cultured cells) is received, amniotic fluid culture/genetic test will be added at an additional charge.
-If chorionic villus specimen (nonconfluent cultured cells) is received, fibroblast culture for genetic test will be added at an additional charge.
For any prenatal specimen that is received, maternal cell contamination testing will be performed at an additional charge.
Special Instructions
Method Name
Sequence Capture and Targeted Next-Generation Sequencing followed by Polymerase Chain Reaction (PCR) and Sanger Sequencing
Reporting Name
F13A1 and B Genes, Full Gene NGSSpecimen Type
VariesSpecimen Minimum Volume
Blood: 1 mL; Amniotic fluid: 10 mL; Other specimen types: See Specimen Required
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Varies | ||
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Clinical Information
Factor XIII deficiency (FXIIID) is a rare hereditary bleeding disorder associated with germline variants in the F13A1 and F13B genes. It is inherited in an autosomal recessive manner with variable expressivity; both male and female patients may be affected. The estimated prevalence is 1 in 2 million individuals.(2-4)
FXIIID caused by homozygous or compound heterozygous variants in F13A1 (FXIII-A deficiency) typically presents as a severe bleeding tendency. Onset of life-threatening symptoms often occurs early with umbilical cord and central nervous system bleeding. Additional symptoms include easy bruising, intramuscular and subcutaneous hematomas, oral mucosal bleeding, epistaxis, perioperative bleeding, and impaired wound healing. Among the rare bleeding disorders, FXIIID appears uniquely associated with pregnancy loss. Affected women have an increased risk of miscarriage, postpartum hemorrhage, menorrhagia, and intraperitoneal bleeding.(2- 7)
Individuals with FXIIID caused by homozygous or compound heterozygous variants in F13B (FXIII-B deficiency) tend to have a milder bleeding tendency, although a severe phenotype can occur.(1,2)
Accurate correlation between genotype and phenotype in FXIIID has proven challenging due to the unpredictable nature and variability of disease symptoms, its rarity, and the limitation of some laboratory assays. Routine coagulation tests are often normal.(2,3,5)
Several causes of acquired (nongenetic) FXIIID should be excluded prior to genetic testing, including leukemia, liver disease, Henoch-Schonlein purpura, inflammatory bowel diseases, disseminated intravascular coagulation, pulmonary embolism, stroke, sepsis, and exposure to valproate. FXIIID also may occur spontaneously in older adults.(1-3)
The United Kingdom Haemophilia Centre Doctors' Organization provides guidelines regarding diagnosis and management for individuals with inherited bleeding disorders, including FXIIID.(8)
Reference Values
An interpretive report will be provided.
Interpretation
All detected variants are evaluated according to American College of Medical Genetics and Genomics recommendations.(9) Variants are classified based on known, predicted, or possible pathogenicity and reported with interpretive comments detailing their potential or known significance.
Day(s) Performed
Varies
Report Available
28 to 42 daysSpecimen Retention Time
Whole blood: 2 weeks (if available); Extracted DNA: 3 months; Amniotic fluid, cultured amniocytes, chorionic villi, cultured chorionic villi: 1 monthPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
81479
88233-Tissue culture, skin, solid tissue biopsy (if appropriate)
88240-Cryopreservation (if appropriate)
88235-Amniotic fluid culture (if appropriate)
81265-Maternal cell contamination (if appropriate)
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| GNF13 | F13A1 and B Genes, Full Gene NGS | 92991-9 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 619146 | Test Description | 62364-5 |
| 619147 | Specimen | 31208-2 |
| 619148 | Source | 31208-2 |
| 619149 | Result Summary | 50397-9 |
| 619150 | Result | 82939-0 |
| 619151 | Interpretation | 69047-9 |
| 619152 | Additional Results | 82939-0 |
| 619153 | Resources | 99622-3 |
| 619154 | Additional Information | 48767-8 |
| 619155 | Method | 85069-3 |
| 619156 | Genes Analyzed | 82939-0 |
| 619157 | Disclaimer | 62364-5 |
| 619158 | Released By | 18771-6 |