GENE REFERENCE / HGNC:3534

F13B

coagulation factor XIII B chain

protein-coding gene1q31.3Gene information

What does this gene do?

The F13B gene provides instructions for making one part, the B subunit, of a protein called factor XIII. This protein is part of a group of related proteins called coagulation factors that are essential for normal blood clotting. They work together as part of the coagulation cascade, which is a series of chemical reactions that forms blood clots in response to injury. After an injury, clots seal off blood vessels to stop bleeding and trigger blood vessel repair. Factor XIII acts at the end of the cascade to strengthen and stabilize newly formed clots, preventing further blood loss.

Factor XIII in the bloodstream is made of two A subunits (produced from the F13A1 gene) and two B subunits (produced from the F13B gene). The role of the B subunits is to carry and stabilize the A subunits, protecting them from being broken down. When a new blood clot forms, the A and B subunits separate from one another, and the A subunits are cut (cleaved) to produce the active form of factor XIII (factor XIIIa). The active protein links together molecules of fibrin, the material that forms the clot, which strengthens the clot and keeps other molecules from breaking it down.

Studies suggest that factor XIII has additional functions, although these are less well understood than its role in blood clotting. Specifically, factor XIII is likely involved in other aspects of wound healing, immune system function, maintaining pregnancy, bone formation, and the growth of new blood vessels (angiogenesis).

Source: MedlinePlus, National Library of Medicine. Source publication: 2020-08-18. Source review: 2015-08.

ClinGen reviews

ClinGen reviews the evidence linking a particular gene to a condition. Each rating below describes the strength of that link. It does not classify a variant in your DNA file.

Condition	Inheritance	Evidence
factor XIII, b subunit, deficiency ofMONDO:0013190 · Evaluated 2020-07-22	Autosomal recessive	DefinitiveHemostasis/Thrombosis Gene Curation Expert Panel

ClinVar records

These numbers show what has been submitted to ClinVar. They cannot tell you how likely you are to have a condition.

Submitted alleles: 203
Submissions for variants in or overlapping this gene: 290
Submissions explicitly reporting this gene: 257
Alleles reported pathogenic / likely pathogenic: 16
VariationIDs with uncertain significance: 121
VariationIDs with conflicting classifications: 9

The rows count different things: alleles, submissions or VariationIDs. Their categories can overlap, so do not add them together. Pathogenic/likely pathogenic counts exclude structural variants that merely overlap a gene. A dash in the source means “not reported,” not zero.

NCBI produces the gene-summary file each week using counts recorded at the start of the month. The numbers may differ from those on the live ClinVar website. Read the field definitions ↗

View this gene in ClinVar ↗

YOUR DNA FILE

Can your DNA file tell you about F13B?

From a DNA test kit (such as 23andMe, AncestryDNA or MyHeritage). These kits check a fixed list of about 600,000 to 700,000 positions across your whole genome. ClinVar lists 16 alleles in F13B reported as pathogenic or likely pathogenic. A kit checks only some of these positions, and often none of them.

From whole genome sequencing (a VCF file). Sequencing reads most of your genome. Your file lists the places where your DNA differs from the reference genome. Some regions are hard to sequence, including parts of some genes that have near-identical copies elsewhere, and a VCF file does not record which positions were read well.

If a variant is not in your file, that does not mean you don’t have it.

What BioDecode checks

BioDecode compares every variant in your file with ClinVar, on your own computer. For each match, it shows the ClinVar classification, the review status and the condition it was reported for. Your file is not uploaded.

A ClinVar classification applies to one particular variant and the condition it was reported for. It does not tell you about other variants in F13B.

BioDecode cannot fill gaps in your test, diagnose a condition or replace clinical testing.

Buy BioDecode See a sample report →Check file compatibility →