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Reviewed February 2012
What is the official name of the FGB gene?
The official name of this gene is “fibrinogen beta chain.”
FGB is the gene's official symbol. The FGB gene is also known by other names, listed below.
Read more about gene names and symbols on the About page.
What is the normal function of the FGB gene?
The FGB gene provides instructions for making a protein called the fibrinogen B beta (Bβ) chain, one piece (subunit) of the fibrinogen protein. This protein is important for blood clot formation (coagulation), which is needed to stop excessive bleeding after injury. To form fibrinogen, the Bβ chain attaches to two other proteins called the fibrinogen A alpha (Aα) and fibrinogen gamma (γ) chains, each produced from different genes. Two sets of this three-protein complex combine to form functional fibrinogen.
For coagulation to occur, another protein called thrombin removes a piece from the Aα and the Bβ subunits of the functional fibrinogen protein (the pieces are called the A and B fibrinopeptides). This process converts fibrinogen to fibrin, the main protein in blood clots. Fibrin proteins attach to each other, forming a stable network that makes up the blood clot.
Does the FGB gene share characteristics with other genes?
The FGB gene belongs to a family of genes called endogenous ligands (endogenous ligands).
A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? in the Handbook.
How are changes in the FGB gene related to health conditions?
Where is the FGB gene located?
Cytogenetic Location: 4q28
Molecular Location on chromosome 4: base pairs 154,562,980 to 154,572,763
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The FGB gene is located on the long (q) arm of chromosome 4 at position 28.
More precisely, the FGB gene is located from base pair 154,562,980 to base pair 154,572,763 on chromosome 4.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about FGB?
You and your healthcare professional may find the following resources about FGB helpful.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
What other names do people use for the FGB gene or gene products?
See How are genetic conditions and genes named? in the Handbook.
Where can I find general information about genes?
The Handbook provides basic information about genetics in clear language.
These links provide additional genetics resources that may be useful.
What glossary definitions help with understanding FGB?
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (6 links)
The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.