major histocompatibility complex, class II, DQ alpha 1
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The HLA-DQA1 gene provides instructions for making a protein that plays a critical role in the immune system. The HLA-DQA1 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.
Normal function
The HLA-DQA1 gene provides instructions for making a protein that plays a critical role in the immune system. The HLA-DQA1 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-DQA1 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-DQA1 gene attaches (binds) to the protein produced from another MHC class II gene, HLA-DQB1. Together, they form a functional protein complex called an antigen-binding DQαβ 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-DQA1 gene, each of which is given a particular number (such as HLA-DQA1*05:01).
Conditions referring to this gene or chromosome
Other names
DC-1 alpha chain
DC-alpha
DQ-A1
FLJ27088
FLJ27328
GSE
HLA class II histocompatibility antigen, DQ alpha 1 chain
HLA class II histocompatibility antigen, DQ alpha 1 chain precursor
HLA class II histocompatibility antigen, DQ(W3) alpha chain
HLA-DCA
HLA-DQA
leucocyte antigen DQA1
leukocyte antigen alpha chain
MGC149527
MHC class II antigen
MHC class II DQA1
MHC class II HLA-D alpha glycoprotein
MHC class II HLA-DQ-alpha-1
MHC class II surface glycoprotein
MHC HLA-DQ alpha
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Further reading and references
- major histocompatibility complex, class II, DQ alpha 1; MedlinePlus, National Library of Medicine.
- Abadie V, Sollid LM, Barreiro LB, Jabri B. Integration of genetic and immunological insights into a model of celiac disease pathogenesis. Annu Rev Immunol. 2011;29:493-525. doi: 10.1146/annurev-immunol-040210-092915.
- da Silva SA, Mazini PS, Reis PG, Sell AM, Tsuneto LT, Peixoto PR, Visentainer JE. HLA-DR and HLA-DQ alleles in patients from the south of Brazil: markers for leprosy susceptibility and resistance. BMC Infect Dis. 2009 Aug 22;9:134. doi: 10.1186/1471-2334-9-134.
- Lipton RB, Drum M, Greeley SA, Danielson KK, Bell GI, Hagopian WA. HLA-DQ haplotypes differ by ethnicity in patients with childhood-onset diabetes. Pediatr Diabetes. 2011 Jun;12(4 Pt 2):388-95. doi: 10.1111/j.1399-5448.2010.00712.x. Epub 2011 Mar 21.
- Noble JA, Valdes AM. Genetics of the HLA region in the prediction of type 1 diabetes. Curr Diab Rep. 2011 Dec;11(6):533-42. doi: 10.1007/s11892-011-0223-x.
- Spraggs CF, Budde LR, Briley LP, Bing N, Cox CJ, King KS, Whittaker JC, Mooser VE, Preston AJ, Stein SH, Cardon LR. HLA-DQA1*02:01 is a major risk factor for lapatinib-induced hepatotoxicity in women with advanced breast cancer. J Clin Oncol. 2011 Feb 20;29(6):667-73. doi: 10.1200/JCO.2010.31.3197. Epub 2011 Jan 18.
- Taylor AK, Lebwohl B, Snyder CL, Green PHR. Celiac Disease. 2008 Jul 3 [updated 2025 Dec 4]. In: Adam MP, Bick S, Mirzaa GM, Wallace SE, Amemiya A, editors. GeneReviews(R) [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2026. Available from http://www.ncbi.nlm.nih.gov/books/NBK1727/
- Tjon JM, van Bergen J, Koning F. Celiac disease: how complicated can it get? Immunogenetics. 2010 Oct;62(10):641-51. doi: 10.1007/s00251-010-0465-9. Epub 2010 Jul 27.
- Uibo R, Tian Z, Gershwin ME. Celiac disease: a model disease for gene-environment interaction. Cell Mol Immunol. 2011 Mar;8(2):93-5. doi: 10.1038/cmi.2010.62. Epub 2011 Feb 14.
- Xun YH, Guo JC, Shi WZ, Shi JP, Liu CL. [Association between HLA-DQA1 gene polymorphism and the outcomes of hepatitis B virus infection]. Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi. 2009 Dec;23(6):430-3. Chinese.
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