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Reviewed January 2012

What is the official name of the FANCG gene?

The official name of this gene is “Fanconi anemia complementation group G.”

FANCG is the gene's official symbol. The FANCG 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 FANCG gene?

The FANCG gene provides instructions for making a protein that is involved in a cell process known as the Fanconi anemia (FA) pathway. The FA pathway is turned on (activated) when the process of making new copies of DNA, called DNA replication, is blocked due to DNA damage. The FA pathway is particularly responsive to a certain type of DNA damage known as interstrand cross-links (ICLs). ICLs occur when two DNA building blocks (nucleotides) on opposite strands of DNA are abnormally attached or linked together, which stops the process of DNA replication. ICLs can be caused by a buildup of toxic substances produced in the body or by treatment with certain cancer therapy drugs.

The FANCG protein is one of a group of proteins known as the FA core complex. The FA core complex is composed of eight FA proteins (including FANCG) and two proteins called Fanconi anemia-associated proteins (FAAPs). This complex activates two proteins, called FANCD2 and FANCI, by attaching a single molecule called ubiquitin to each of them (a process called monoubiquitination). The activation of these two proteins, which attach (bind) together to form the ID protein complex, attracts DNA repair proteins to the area of DNA damage so the error can be corrected and DNA replication can continue.

Does the FANCG gene share characteristics with other genes?

The FANCG gene belongs to a family of genes called FANC (Fanconi anemia, complementation groups).

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 FANCG gene related to health conditions?

Fanconi anemia - caused by mutations in the FANCG gene

More than 50 mutations in the FANCG gene have been found to cause Fanconi anemia, a disorder characterized by a decrease in bone marrow function, an increased cancer risk, and physical abnormalities. About 10 percent of all cases of Fanconi anemia are caused by mutations in the FANCG gene. When Fanconi anemia results from mutations in this gene, it is often associated with a more severe shortage of blood cells than when the condition is caused by mutations in other genes.

Most mutations in the FANCG gene that cause Fanconi anemia lead to absent or reduced protein function. Individuals who have mutations that lead to no protein production typically have more severe signs or symptoms than people who have mutations that allow for some FANCG protein production. Due to a decrease in FANCG protein function, the FA core complex cannot function and the entire FA pathway is disrupted. As a result, DNA damage is not repaired efficiently and ICLs build up over time. The ICLs stall DNA replication, ultimately resulting in either abnormal cell death due to an inability make new DNA molecules or uncontrolled cell growth due to a lack of DNA repair processes. Cells that divide quickly, such as bone marrow cells and cells of the developing fetus, are particularly affected. The death of these cells results in the decrease in blood cells and the physical abnormalities characteristic of Fanconi anemia. When the buildup of errors in DNA leads to uncontrolled cell growth, affected individuals can develop leukemia or other cancers.

Where is the FANCG gene located?

Cytogenetic Location: 9p13

Molecular Location on chromosome 9: base pairs 35,073,838 to 35,080,016

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBIThis link leads to a site outside Genetics Home Reference.)

The FANCG gene is located on the short (p) arm of chromosome 9 at position 13.

The FANCG gene is located on the short (p) arm of chromosome 9 at position 13.

More precisely, the FANCG gene is located from base pair 35,073,838 to base pair 35,080,016 on chromosome 9.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about FANCG?

You and your healthcare professional may find the following resources about FANCG 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 FANCG gene or gene products?

  • FAG
  • Fanconi anemia, complementation group G
  • XRCC9

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 FANCG?

anemia ; bone marrow ; cancer ; cell ; DNA ; DNA damage ; DNA repair ; DNA replication ; fetus ; gene ; leukemia ; molecule ; protein ; toxic ; ubiquitin

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.

See also Understanding Medical Terminology.

References (8 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.

Reviewed: January 2012
Published: February 8, 2016