HLA-DQ5

heteroisoform
isoformgroup = HLA-DQ5
polymer_type = MHC Class II, DQ cell surface antigen


image_source = Illustration of HLA-DQ with gliadin peptide in the binding pocket.
isoformCount = 3
subunit1 = DQA1
subunit2 = DQB1
isoform1 = DQ α^1.1β^5.1
nick1 = DQ5.1
allele1a = HQAA|0101
allele1b = *0501
isoform2 = DQ α^1.2β^5.2
nick2 = DQ5.2
allele2a = HQAA|0102
allele2b = *0502
isoform3 = DQ α^1.4β^5.3
nick3 = DQ5.3
allele3a = HQAA|0104
allele3b = *0503
isoform4 = DQ α^1.2β^5.4
nick4 = DQ5.4
allele4a = *0102
allele4b = *0504

HLA-DQ4 (DQ5) is a human leukocyte antigen serotype subgroup within HLA-DQ(DQ) serotypes. The serotype is determined by the antibody recognition of β^5.x subset of DQ β-chains. The β-chain of DQ is encoded by HLA-DQB1 locus and DQ5 are encoded by the HLA-DQB1*05 allele group. This group currently contains 4 common alleles, DQB1*0501, *0502, , *0503, and *0504. HLA-DQ5 and HLA-DQB1*05 are almost synonymous in meaning. DQ5 β-chains combine with α-chains, encoded by genetically linked HLA-DQA1 alleles, to form the - isoforms. These isoforms, are all HLA-DQ1 encoded by the DQA1*01 allele group.

erology

The efficiency of DQ1 recognition relative to DQ5 and DQ6 is listed above. SinceDQ1 recognizes alpha, the DQ5 and DQ6 recognition are to beta chain. Meaningthat DQ1 is corecognized with DQ5 and DQ6. Efficient recognition of a genotyped allele approaches 100%. Compared to DQ2 serotyping of DQB1*0201 positive individuals (98%), the efficiency of DQ5 recognition is relatively low and error prone.

While DQ5 recognizes DQB1*05 alleles more efficiently than DQ1, the serotyping is rather poor method of typing for transplantation or disease association prediction or study.

Disease associations

By serotype

DQ5 is negatively associated with (protective against) idiopathic nephrotic syndrome in Polish children,cite journal | author = Krasowska-Kwiecień A, Sancewicz-Pach K, Moczulska A | title = Idiopathic nephrotic syndrome in Polish children - its variants and associations with HLA | journal = Pediatr. Nephrol. | volume = 21 | issue = 12 | pages = 1837–46 | year = 2006 | pmid = 16967287 | doi = 10.1007/s00467-006-0271-7] and adrenocortical failure (Addison's disease)cite journal | author = Myhre AG, Undlien DE, Løvås K, "et al" | title = Autoimmune adrenocortical failure in Norway autoantibodies and human leukocyte antigen class II associations related to clinical features | journal = J. Clin. Endocrinol. Metab. | volume = 87 | issue = 2 | pages = 618–23 | year = 2002 | pmid = 11836294 | doi = ] .

A study on the relationship between HLA-DR, DQ antigen, and intracranial aneurysm in the Han nationality show DQ5 more likelycite journal | author = Wang JF, Zhang D, Zhao JZ, Jia BX, Bi RM | title = A study on the relationship between HLA-DR, DQ antigen, and intracranial aneurysm in the Han nationality | journal = Surgical neurology | volume = 66 Suppl 1 | issue = | pages = S25–8; discussion S28–9 | year = 2006 | pmid = 16904993 | doi = 10.1016/j.surneu.2006.06.048] , AIDP type of Guillain Barré syndrome,cite journal | author = Guo L, Wang W, Li C, Liu R, Wang G | title = [The association between HLA typing and different subtypes of Guillain Barré syndrome] | language = Chinese | journal = Zhonghua Nei Ke Za Zhi | volume = 41 | issue = 6 | pages = 381–3 | year = 2002 | pmid = 12137599 | doi = ] and irritable bowel disease cite journal | author = Trachtenberg EA, Yang H, Hayes E, "et al" | title = HLA class II haplotype associations with inflammatory bowel disease in Jewish (Ashkenazi) and non-Jewish caucasian populations | journal = Hum. Immunol. | volume = 61 | issue = 3 | pages = 326–33 | year = 2000 | pmid = 10689124 | doi = ] but not crohn's disease in the same (jewish) population. Other studies show DQ5 is associated with extrachromosomal manifestations of Crohn's.cite journal | author = Hesresbach D, Alizadeh M, Bretagne JF, "et al" | title = Investigation of the association of major histocompatibility complex genes, including HLA class I, class II and TAP genes, with clinical forms of Crohn's disease | journal = Eur. J. Immunogenet. | volume = 23 | issue = 2 | pages = 141–51 | year = 1996 | pmid = 8732477 | doi = ]

DQ5 appears to be associated with analgesic intolerance.cite journal | author = Kalyoncu AF, Karakaya G, Yilmaz E, Balci B, Karaduman A, Yasavul U | title = Analgesic intolerance with or without bronchial asthma: is there a marker? | journal = Journal of investigational allergology & clinical immunology : official organ of the International Association of Asthmology (INTERASMA) and Sociedad Latinoamericana de Alergia e Inmunología | volume = 13 | issue = 3 | pages = 162–9 | year = 2003 | pmid = 14635465 | doi = ]

By haplotype

MuSK antibody-positive myasthenia gravis HLA-DR14-DQ5 cite journal | author = Niks EH, Kuks JB, Roep BO, "et al" | title = Strong association of MuSK antibody-positive myasthenia gravis and HLA-DR14-DQ5 | journal = Neurology | volume = 66 | issue = 11 | pages = 1772–4 | year = 2006 | pmid = 16769963 | doi = 10.1212/01.wnl.0000218159.79769.5c] , probably DRB1*1402 : DQA1*0104 : DQB1*0503 (DR14-DQ5). DR1-DQ5 is associated with acid anyhydride sensitivity.cite journal | author = Jones MG, Nielsen J, Welch J, "et al" | title = Association of HLA-DQ5 and HLA-DR1 with sensitization to organic acid anhydrides | journal = Clin. Exp. Allergy | volume = 34 | issue = 5 | pages = 812–6 | year = 2004 | pmid = 15144476 | doi = 10.1111/j.1365-2222.2004.1956.x]

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