HLA-DQ6

heteroisoform
isoformgroup = HLA-DQ6
polymer_type = MHC Class II, DQ cell surface antigen


image_source = Illustration of HLA-DQ with bound peptide
isoformCount = 4
subunit1 = DQA1
subunit2 = DQB1
isoform1 = DQ α^1.3β^6.1
nick1 = DQ6.1
allele1a = HQAA|0103
allele1b = *0601
isoform2 = DQ α^1.2β^6.2
nick2 = DQ6.2
allele2a = HQAA|0102
allele2b = *0602
isoform3 = DQ α^1.3β^6.3
nick3 = DQ6.3
allele3a = *0103
allele3b = *0603
isoform4 = DQ α^1.2β^6.4
nick4 = DQ6.4
allele4a = *0102
allele4b = *0604
rareIsoforms = 3
risoform1 = DQ α^1.2β^6.3
rnick1 = DQ6.3v
rallele1a = *0102
rallele1b = *0603
risoform2 = DQ α^1.3β^6.2
rnick2 = DQ6.2v
rallele2a = *0103
rallele2b = *0602
risoform3 = DQ α^1.2β^6.9
rnick3 = DQ6.9
rallele3a = *0102
rallele3b = *0609

HLA-DQ6 (DQ6) is a human leukocyte antigen serotype within HLA-DQ (DQ) serotype group. The serotype is determined by the antibody recognition of β⁶ subset of DQ β-chains. The β-chain of DQ s are encoded by HLA-DQB1 locus and DQ6 are encoded by the HLA-DQB1*06 allele group. This group currently contains many common alleles, DQB1*0602 is the most common. HLA-DQ6 and DQB1*06 are almost synonymous in meaning. DQ6 β-chains combine with α-chains, encoded by genetically linked HLA-DQA1 alleles, to form the - isoforms. For DQ6, however, cis-isoform pairing only occurs with DQ1 α-chains. The are many haplotypes of DQ6.

erology

DQB1*0602

DQB1*0602 is commonly linked to DQA1*0102 to form 6.2 haplotype. DQ6.2 and is common from Central Asia into Western Europe, *0602 is also linked to DQA1*0103 in parts of Asia.

DQB1*0609

This alleles if found in Africa and proximal regions of Eurasia.

Haplotypes and disease

Susceptibility to "Leptospirosis" infection was found associated with undifferentiated DQ6.cite journal |author=Lingappa J, Kuffner T, Tappero J, "et al" |title=HLA-DQ6 and ingestion of contaminated water: possible gene-environment interaction in an outbreak of Leptospirosis |journal=Genes Immun. |volume=5 |issue=3 |pages=197–202 |year=2004 |month=May |pmid=15014429 |doi=10.1038/sj.gene.6364058 |url=] Whereas DQ6 was protective against death (or need for liver transplantion) in primary sclerosing cholangitis.cite journal |author=Boberg KM, Spurkland A, Rocca G, "et al" |title=The HLA-DR3,DQ2 heterozygous genotype is associated with an accelerated progression of primary sclerosing cholangitis |journal=Scand. J. Gastroenterol. |volume=36 |issue=8 |pages=886–90 |year=2001 |month=August |pmid=11495087 |doi= |url=]

DQ6.1

DQA1*0103:DQB1*0601 (DQ6.1) is found at increased freqeuncies in Asia and is almostabsent in Western Europe. It confers protection from narcolepsycite journal | author = Hong SC, Lin L, Lo B, "et al" | title = DQB1*0301 and DQB1*0601 modulate narcolepsy susceptibility in Koreans | journal = Hum. Immunol. | volume = 68 | issue = 1 | pages = 59–68 | year = 2007 | pmid = 17207713 | doi = 10.1016/j.humimm.2006.10.006] , juvenile diabetescite journal | author = Sang Y, Yan C, Zhu C, Ni G | title = Relationship between HLA-DRB1 and DQ alleles and the genetic susceptibility to type 1 diabetes | journal = Chin. Med. J. | volume = 114 | issue = 4 | pages = 407–9 | year = 2001 | pmid = 11780465 | doi = ] cite journal | author = Saruhan-Direskeneli G, Uyar FA, Bas F, "et al" | title = HLA-DR and -DQ associations with insulin-dependent diabetes mellitus in a population of Turkey | journal = Hum. Immunol. | volume = 61 | issue = 3 | pages = 296–302 | year = 2000 | pmid = 10689119 | doi = ] , Vogt-Koyanagi-Harada (VKH) syndromecite journal | author = Kim MH, Seong MC, Kwak NH, "et al" | title = Association of HLA with Vogt-Koyanagi-Harada syndrome in Koreans | journal = Am. J. Ophthalmol. | volume = 129 | issue = 2 | pages = 173–7 | year = 2000 | pmid = 10682969 | doi = ] , pemphigus vulgariscite journal | author = Niizeki H, Inoko H, Mizuki N, "et al" | title = HLA-DQA1, -DQB1 and -DRB1 genotyping in Japanese pemphigus vulgaris patients by the PCR-RFLP method | journal = Tissue Antigens | volume = 44 | issue = 4 | pages = 248–51 | year = 1994 | pmid = 7871526 | doi = ] , multiple sclerosiscite journal | author = Amirzargar A, Mytilineos J, Yousefipour A, "et al" | title = HLA class II (DRB1, DQA1 and DQB1) associated genetic susceptibility in Iranian multiple sclerosis (MS) patients | journal = Eur. J. Immunogenet. | volume = 25 | issue = 4 | pages = 297–301 | year = 1998 | pmid = 9777330 | doi = ] , myasthenia gravis.

DQ6.2

DQ6.2 (DQA1*0102 : DQB1*0602) is commonly linked to DR15 and as such is part of the HLA B7-DR15-DQ6 haplotype. This haplotype is considered to be the longest multigene haplotype known within the human genome as it covers over 4.7 million nucleotides. The DR15-DQ6.2 haplotype is the most common DR-DQ haplotype in Europe, and approximately 30% of Americans carry at least DQ6.2. The haplotype is even more common in Central Asia.

DQ6.2 associations with disease

For "myasthenia gravis", recognition α34-49 of AChR increased with DQ6.2cite journal | author = Deitiker PR, Oshima M, Smith RG, Mosier DR, Atassi MZ | title = Subtle differences in HLA DQ haplotype-associated presentation of AChR alpha-chain peptides may suffice to mediate myasthenia gravis | journal = Autoimmunity | volume = 39 | issue = 4 | pages = 277–88 | year = 2006 | pmid = 16891216 | doi = 10.1080/08916930600738581] . DQA1*0102 increases risk cervical cancer.cite journal |author=Ghaderi M, Nikitina L, Peacock CS, "et al" |title=Tumor necrosis factor a-11 and DR15-DQ6 (B*0602) haplotype increase the risk for cervical intraepithelial neoplasia in human papillomavirus 16 seropositive women in Northern Sweden |journal=Cancer Epidemiol. Biomarkers Prev. |volume=9 |issue=10 |pages=1067–70 |year=2000 |month=October |pmid=11045789 |doi= |url=http://cebp.aacrjournals.org/cgi/pmidlookup?view=long&pmid=11045789] cite journal | author = Schiff MA, Apple RJ, Lin P, Nelson JL, Wheeler CM, Becker TM | title = HLA alleles and risk of cervical intraepithelial neoplasia among southwestern American Indian women | journal = Hum. Immunol. | volume = 66 | issue = 10 | pages = 1050–6 | year = 2005 | pmid = 16386646 | doi = 10.1016/j.humimm.2005.09.002] In multiple sclerosis DQA1*0102 was the most frequent allele and DQB1*0602 increased significantly in the MS patients.cite journal |author=Kolstad A, Hannestad K, Vandvik B, Vartdal F |title=Multiple sclerosis patients have a high frequency of an HLA-DQ beta epitope defined by a human-human hybridoma antibody |journal=Tissue Antigens |volume=33 |issue=5 |pages=546–9 |year=1989 |month=May |pmid=2477915 |doi= |url=] cite journal | author = Amirzargar AA, Tabasi A, Khosravi F, "et al" | title = Optic neuritis, multiple sclerosis and human leukocyte antigen: results of a 4-year follow-up study | journal = Eur. J. Neurol. | volume = 12 | issue = 1 | pages = 25–30 | year = 2005 | pmid = 15613143 | doi = 10.1111/j.1468-1331.2004.00901.x] cite journal | author = Fernández O, Fernández V, Alonso A, "et al" | title = DQB1*0602 allele shows a strong association with multiple sclerosis in patients in Malaga, Spain | journal = J. Neurol. | volume = 251 | issue = 4 | pages = 440–4 | year = 2004 | pmid = 15083289 | doi = 10.1007/s00415-004-0350-2]

Protective effects of DQ6.2

In "primary biliary cirrhosis" DQ6.2 appears to have a negative association with disease.cite journal | author = Mullarkey ME, Stevens AM, McDonnell WM, "et al" | title = Human leukocyte antigen class II alleles in Caucasian women with primary biliary cirrhosis | journal = Tissue Antigens | volume = 65 | issue = 2 | pages = 199–205 | year = 2005 | pmid = 15713222 | doi = 10.1111/j.1399-0039.2005.00351.x] DQ6.2 also appears to have a protective effect in juvenile diabetes.cite journal |author=Rayner ML, Kelly MA, Mijovic CH, Barnett AH |title=Sequencing of the second exon of the MHC class II DQ6 alleles in patients with type 1 diabetes |journal=Autoimmunity |volume=35 |issue=2 |pages=155–7 |year=2002 |month=March |pmid=12071438 |doi= |url=] cite journal |author=Pociot F, McDermott MF |title=Genetics of type 1 diabetes mellitus |journal=Genes Immun. |volume=3 |issue=5 |pages=235–49 |year=2002 |month=August |pmid=12140742 |doi=10.1038/sj.gene.6363875 |url=] DQ6.2 is alos protective against infantile spasms in mestizos.cite journal |author=Suastegui RA, De La Rosa G, Carranza JM, Gonzalez-Astiazaran A, Gorodezky C |title=Contribution of the MHC class II antigens to the etiology of infantile spasm in Mexican Mestizos |journal=Epilepsia |volume=42 |issue=2 |pages=210–5 |year=2001 |month=February |pmid=11240591 |doi= |url=http://www.blackwell-synergy.com/openurl?genre=article&sid=nlm:pubmed&issn=0013-9580&date=2001&volume=42&issue=2&spage=210]

DQ6.3

DQ6.3 (DQA1*0103 : DQB1*0603) is found in northcentral Europe at moderate frequencies, it is a protective against many autoimmune diseases. It also affords some protection to HIV infection.cite journal |author=Achord AP, Lewis RE, Brackin MN, Henderson H, Cruse JM |title=HIV-1 disease association with HLA-DQ antigens in African Americans and Caucasians |journal=Pathobiology |volume=64 |issue=4 |pages=204–8 |year=1996 |pmid=9031330 |doi= |url=]

DQ6.4

DQ6.4 (DQA1*0102 : DQB1*0604) might be associated with thymoma-induced myastenia gravis [cite journal | author = Vieira M, Caillat-Zucman S, Gajdos P, Cohen-Kaminsky S, Casteur A, Bach J | title = Identification by genomic typing of non-DR3 HLA class II genes associated with myasthenia gravis. | journal = J Neuroimmunol | volume = 47 | issue = 2 | pages = 115–22 | year = 1993 | pmid = 8370765 | doi = 10.1016/0165-5728(93)90021-P] .

References