HLA-DR3

HLA-DR3 is composed to the HLA-DR17 and HLA-DR18 split 'antigens' serotypes. DR3 is a component gene-allele of the AH8.1 haplotype in Northern and Western Europeans. Genes between B8 and DR3 on this haplotype are frequently associated with autoimmune disease.

=Serology=

Some DR3 also react with HLA-DR17 and/or HLA-DR18. The DRB1*0304 primarily reacts with DR3. The serotypes of *0305, *0306, *0308 to *0331 are unknown.

=Disease associations=

By serotype

HLA-DR3 is associated with early-age onset myasthenia gravis, primary sclerosing cholangitis,cite journal | author = Wiencke K, Karlsen TH, Boberg KM, "et al" | title = Primary sclerosing cholangitis is associated with extended HLA-DR3 and HLA-DR6 haplotypes | journal = Tissue Antigens | volume = 69 | issue = 2 | pages = 161–9 | year = 2007 | pmid = 17257319 | doi = 10.1111/j.1399-0039.2006.00738.x] and opportunistic infections in AIDScite journal | author = Pollack MS, Gold J, Metroka CE, Safai B, Dupont B | title = HLA-A,B,C and DR antigen frequencies in acquired immunodeficiency syndrome (AIDS) patients with opportunistic infections | journal = Hum. Immunol. | volume = 11 | issue = 2 | pages = 99–103 | year = 1984 | pmid = 6333416 | doi = ] , but lowered risk for cancerscite journal | author = Mann DL, Murray C, O'Donnell M, Blattner WA, Goedert JJ | title = HLA antigen frequencies in HIV-1-related Kaposi's sarcoma | journal = J. Acquir. Immune Defic. Syndr. | volume = 3 Suppl 1 | issue = | pages = S51–5 | year = 1990 | pmid = 2395088 | doi = ] .

By allele

DRB1*0301 (see HLA-DR17)

DRB1*0302 (See HLA-DR18)

DRB1*0304 is associated it graves diseasecite journal | pmid = 10468973]

By haplotypes

DR3 and/or DQ2 is associated with Moreen's ulceration [cite journal | author = Taylor C, Smith S, Morgan C, Stephenson S, Key T, Srinivasan M, Cunningham E, Watson P | title = HLA and Mooren's ulceration. | journal = Br J Ophthalmol | volume = 84 | issue = 1 | pages = 72–5 | year = 2000 | pmid = 10611103 | doi = 10.1136/bjo.84.1.72] , "bout onset" multiple sclerosis [cite journal | author = Weinshenker B, Santrach P, Bissonet A, McDonnell S, Schaid D, Moore S, Rodriguez M | title = Major histocompatibility complex class II alleles and the course and outcome of MS: a population-based study. | journal = Neurology | volume = 51 | issue = 3 | pages = 742–7 | year = 1998 | pmid = 9748020] , Grave's disease [cite journal | author = Ratanachaiyavong S, Lloyd L, Darke C, McGregor A | title = MHC-extended haplotypes in families of patients with Graves' disease. | journal = Hum Immunol | volume = 36 | issue = 2 | pages = 99–111 | year = 1993 | pmid = 8096501 | doi = 10.1016/0198-8859(93)90112-E] and systemic lupus erythematosus [cite journal | author = Tjernström F, Hellmer G, Nived O, Truedsson L, Sturfelt G | title = Synergetic effect between interleukin-1 receptor antagonist allele (IL1RN*2) and MHC class II (DR17,DQ2) in determining susceptibility to systemic lupus erythematosus. | journal = Lupus | volume = 8 | issue = 2 | pages = 103–8 | year = 1999 | pmid = 10192503 | doi = 10.1191/096120399678847560]

DR3-DQ2 linkage is associated with coeliac disease, dermatitis herpetiformis, juvenile diabetes. DR3-DR2 is the serological marker for HLA-DQ2.5cis isoform. Although it cannot identify the alpha ".5" chain of HLA DQ, DQA1*0501 gene is almost always found within the DR3-DQ2 haplotype Eurasia (however is older studies DQA1*0505 is commonly confused with DQA1*0501)
cite journal |author=Pera C, Delfino L, Longo A, Pistillo MP, Ferrara GB |title=Novel associations among HLA-DQA1 and -DQB1 alleles, revealed by high-resolution sequence-based typing (SBT) |journal=Tissue Antigens |volume=55 |issue=3 |pages=275–9 |year=2000 |month=March |pmid=10777105 |doi= |url=http://www.blackwell-synergy.com/openurl?genre=article&sid=nlm:pubmed&issn=0001-2815&date=2000&volume=55&issue=3&spage=275]

=Genetic linkage=DR3 is genetically linked to HLA-DR52, DRB3*0202 allele, and HLA-DQ2 (DQ2.5).

=References=