HLA-DQB1

Major histocompatibility complex, class II, DQ beta 1
Structure of HLA-DQB1 (green) complexed with HLA-DQA1 (cyan) and HCRT (magenta) based on PDB: 1uvq​.
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 1JK8​, 1NBN​, 1S9V​, 1UVQ​, 2NNA​, 4GG6​, 4OZF​, 4OZG​, 4OZH​, 4OZI​
Identifiers
Symbols	HLA-DQB1 ; CELIAC1; HLA-DQB; IDDM1
External IDs	OMIM: 604305 HomoloGene: 1603 GeneCards: HLA-DQB1 Gene
Gene ontology Molecular function • MHC class II receptor activity • peptide antigen binding Cellular component • Golgi membrane • lysosomal membrane • plasma membrane • endosome membrane • ER to Golgi transport vesicle membrane • membrane • transport vesicle membrane • endocytic vesicle membrane • clathrin-coated endocytic vesicle membrane • trans-Golgi network membrane • MHC class II protein complex • integral component of lumenal side of endoplasmic reticulum membrane Biological process • immunoglobulin production involved in immunoglobulin mediated immune response • humoral immune response mediated by circulating immunoglobulin • immune response • cytokine-mediated signaling pathway • antigen processing and presentation of exogenous peptide antigen via MHC class II • T cell costimulation • T cell receptor signaling pathway • interferon-gamma-mediated signaling pathway Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	3119	14961
Ensembl	ENSG00000179344	ENSMUSG00000073421
UniProt	P01920	P14483
RefSeq (mRNA)	NM_001243961	NM_207105
RefSeq (protein)	NP_001230890	NP_996988
Location (UCSC)	Chr 6: 32.66 – 32.67 Mb	Chr 17: 34.26 – 34.27 Mb
PubMed search

Major histocompatibility complex, class II, DQ beta 1, also known as HLA-DQB1, is a human gene and also denotes the genetic locus that contains this gene.^[1] The protein encoded by this gene is one of two proteins that are required to form the DQ heterodimer, a cell surface receptor essential to the function of the immune system.

Function

HLA-DQB1 belongs to the HLA class II beta chain paralogues. This class II molecule is a heterodimer consisting of an alpha (DQA) and a beta chain (DQB), both anchored in the membrane. It plays a central role in the immune system by presenting peptides derived from extracellular proteins. Class II molecules are expressed in antigen-presenting cells (APC: B lymphocytes, dendritic cells, macrophages).^[1]

Gene structure and polymorphisms

The beta chain is approximately 26-28 kDa and it contains 5 exons. Exon one encodes the leader peptide, exons 2 and 3 encode the two extracellular protein domains, exon 4 encodes the transmembrane domain, and exon 5 encodes the cytoplasmic tail. Within the DQ molecule, both the alpha chain and the beta chain contain the polymorphisms specifying the peptide binding specificities, resulting in up to 4 different molecules. Typing for these polymorphisms is routinely done for bone marrow transplantation.^[1][2]

Disease association

Diabetes

Several alleles of HLA-DQB1 are associated with an increased risk of developing type 1 diabetes.^[3][4][5] The locus also has the genetic name IDDM1 as it is the highest genetic risk for type 1 diabetes. Again the DQB1*0201 and DQB1*0302 alleles, particularly the phenotype DQB1*0201/*0302 has a high risk of late onset type 1 diabetes. The risk is partially shared with the HLA-DR locus (DR3 and DR4 serotypes).

Celiac disease

Celiac1 is a genetic name for DQB1, the HLA DQB1*0201, *0202, and *0302 encode genes that mediate the autoimmune coeliac disease. Homozygotes of DQB1*0201 have a higher risk of developing the celiac disease, relative to any other genetic locus.^[6]

Multiple sclerosis

Certain HLA-DQB1 alleles are also linked to a modest increased risk of multiple sclerosis.^[7][8]

Narcolepsy

Other HLA-DQB1 alleles are associated with a predisposition to narcolepsy,^[9] specifically HLA-DQB1*0602, which is carried by over 90% of patients with narcolepsy-cataplexy.^[10]

Alleles

HLA-DQB1 alleles

Serotype	DQB1 allele
DQ2	*0201
	*0202
	*0203
DQ4	*0401
	*0402
DQ5	*0501
	*0502
	*0503
	*0504
DQ6	*0601
	*0602
	*0603
	*0604
	*0605
	*0609
DQ7	*0301
	*0304
DQ8	*0302
	*0305
DQ9	*0303

See also

• Major histocompatibility complex
• Human leukocyte antigen
• HLA-DQ

References

1. "Entrez Gene: HLA-DQB1 major histocompatibility complex, class II, DQ beta 1".
2. Lau M, Terasaki PI, Park MS (1994). "International Cell Exchange, 1994". Clin Transpl: 467–88. PMID 7547576.
3. Todd JA (April 1990). "Genetic control of autoimmunity in type 1 diabetes". Immunol. Today 11 (4): 122–9. doi:10.1016/0167-5699(90)90049-F. PMID 2187469.
4. Todd JA (March 1997). "Genetics of type 1 diabetes". Pathol. Biol. 45 (3): 219–27. PMID 9296067.
5. Redondo MJ, Fain PR, Eisenbarth GS (2001). "Genetics of type 1A diabetes". Recent Prog. Horm. Res. 56: 69–89. doi:10.1210/rp.56.1.69. PMID 11237226.
6. Murray JA, Moore SB, Van Dyke CT, et al. (December 2007). "HLA DQ gene dosage and risk and severity of celiac disease". Clin. Gastroenterol. Hepatol. 5 (12): 1406–12. doi:10.1016/j.cgh.2007.08.013. PMC 2175211. PMID 17919990.
7. Dyment DA, Sadovnick AD, Ebers GC, Sadnovich AD (1997). "Genetics of multiple sclerosis". Hum. Mol. Genet. 6 (10): 1693–8. doi:10.1093/hmg/6.10.1693. PMID 9300661.
8. Schmidt H, Williamson D, Ashley-Koch A (May 2007). "HLA-DR15 haplotype and multiple sclerosis: a HuGE review". Am. J. Epidemiol. 165 (10): 1097–109. doi:10.1093/aje/kwk118. PMID 17329717.
9. Kadotani H, Faraco J, Mignot E (May 1998). "Genetic studies in the sleep disorder narcolepsy". Genome Res. 8 (5): 427–34. doi:10.1101/gr.8.5.427. PMID 9582188.
10. "Narcolepsy Research - FAQs". Retrieved 3 January 2014.