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Reviewed April 2011
What is the official name of the NBN gene?
The official name of this gene is “nibrin.”
NBN is the gene's official symbol. The NBN 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 NBN gene?
The NBN gene provides instructions for making a protein called nibrin. This protein is involved in several critical cellular functions, including the repair of damaged DNA.
Nibrin interacts with two other proteins, produced from the MRE11A and RAD50 genes, as part of a larger protein complex. Nibrin regulates the activity of this complex by carrying the MRE11A and RAD50 proteins into the cell's nucleus and guiding them to sites of DNA damage. The proteins work together to mend broken strands of DNA. DNA can be damaged by agents such as toxic chemicals or radiation, and breaks in DNA strands also occur naturally when chromosomes exchange genetic material in preparation for cell division. Repairing DNA prevents cells from accumulating genetic damage that may cause them to die or to divide uncontrollably.
The MRE11A/RAD50/NBN complex interacts with the protein produced from the ATM gene, which plays an essential role in recognizing broken strands of DNA and coordinating their repair. The MRE11A/RAD50/NBN complex helps maintain the stability of a cell's genetic information through its roles in repairing damaged DNA and regulating cell division. Because these functions are critical for preventing the formation of cancerous tumors, nibrin is described as a tumor suppressor.
How are changes in the NBN gene related to health conditions?
Genetics Home Reference provides additional information about these conditions associated with changes in the NBN gene:
Where is the NBN gene located?
Cytogenetic Location: 8q21
Molecular Location on chromosome 8: base pairs 89,933,336 to 89,984,733
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The NBN gene is located on the long (q) arm of chromosome 8 at position 21.
More precisely, the NBN gene is located from base pair 89,933,336 to base pair 89,984,733 on chromosome 8.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about NBN?
You and your healthcare professional may find the following resources about NBN 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 NBN 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 NBN?
cancer ; cell ; cell cycle ; cell division ; cell proliferation ; DNA ; DNA damage ; gene ; immune system ; inherited ; leukemia ; melanoma ; mutation ; nucleus ; ovarian ; proliferation ; prostate ; protein ; radiation ; syndrome ; telomere ; toxic ; tumor
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (12 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.