About Site Map Contact Us
|A service of the U.S. National Library of Medicine®|
On this page:
Reviewed September 2013
What is the official name of the HLA-DRB1 gene?
The official name of this gene is “major histocompatibility complex, class II, DR beta 1.”
HLA-DRB1 is the gene's official symbol. The HLA-DRB1 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 HLA-DRB1 gene?
The HLA-DRB1 gene provides instructions for making a protein that plays a critical role in the immune system. The HLA-DRB1 gene is part of a family of genes called the human leukocyte antigen (HLA) complex. The HLA complex helps the immune system distinguish the body's own proteins from proteins made by foreign invaders such as viruses and bacteria.
The HLA complex is the human version of the major histocompatibility complex (MHC), a gene family that occurs in many species. The HLA-DRB1 gene belongs to a group of MHC genes called MHC class II. MHC class II genes provide instructions for making proteins that are present on the surface of certain immune system cells. These proteins attach to protein fragments (peptides) outside the cell. MHC class II proteins display these peptides to the immune system. If the immune system recognizes the peptides as foreign (such as viral or bacterial peptides), it triggers a response to attack the invading viruses or bacteria.
The protein produced from the HLA-DRB1 gene, called the beta chain, attaches (binds) to another protein called the alpha chain, which is produced from the HLA-DRA gene. Together, they form a functional protein complex called the HLA-DR antigen-binding heterodimer. This complex displays foreign peptides to the immune system to trigger the body's immune response.
Each MHC class II gene has many possible variations, allowing the immune system to react to a wide range of foreign invaders. Researchers have identified hundreds of different versions (alleles) of the HLA-DRB1 gene, each of which is given a particular number (such as HLA-DRB1*04:01).
Does the HLA-DRB1 gene share characteristics with other genes?
The HLA-DRB1 gene belongs to a family of genes called HLA (histocompatibility complex genes). It also belongs to a family of genes called immunoglobulin superfamily, C1-set domain containing (immunoglobulin superfamily, C1-set domain containing).
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 HLA-DRB1 gene related to health conditions?
Genetics Home Reference provides information about these additional conditions, which are also associated with changes in the HLA-DRB1 gene:
Where is the HLA-DRB1 gene located?
Cytogenetic Location: 6p21.3
Molecular Location on chromosome 6: base pairs 32,546,545 to 32,557,612
The HLA-DRB1 gene is located on the short (p) arm of chromosome 6 at position 21.3.
More precisely, the HLA-DRB1 gene is located from base pair 32,546,545 to base pair 32,557,612 on chromosome 6.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about HLA-DRB1?
You and your healthcare professional may find the following resources about HLA-DRB1 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 HLA-DRB1 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 HLA-DRB1?
acids ; arthritis ; autoimmune ; bacteria ; cell ; central nervous system ; chronic ; class ; diabetes ; gene ; haplotype ; HLA ; hormone ; idiopathic ; immune response ; immune system ; inflammation ; insulin ; juvenile ; leukocyte ; lymphocyte ; MHC ; mucous ; myelin sheath ; nervous system ; pancreas ; peptide ; protein ; sarcoidosis ; sclerosis
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (11 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.