Biology:HLA-DQ3

From HandWiki
Illustration of HLA-DQ with peptide in the binding pocket
major histocompatibility complex, class II, DQ3
Haplotypes DQA1*0303:DQB1*0301 DQA1*0401:DQB1*0301 DQA1*0505:DQB1*0301 DQA1*0601:DQB1*0301 DQA1*03:DQB1*0302 DQA1*0301:DQB1*0303
Structure (See HLA-DQ)
Identifiers
alpha 1 *0301 *0302 *0303 *0401 *0505 *0601
Symbol(s) HLA-DQA1[yes|permanent dead link|dead link}}]
EBI-HLA DQA1*0301
EBI-HLA DQA1*0302
EBI-HLA DQA1*0303
EBI-HLA DQA1*0401
EBI-HLA DQA1*0505
Identifiers
beta 1 *0301 *0302 *0303
Symbol(s) HLA-DQB1
EBI-HLA DQB1*0301
EBI-HLA DQB1*0302
EBI-HLA DQB1*0303
Shared data
Locus chr.6 6p21.31

Within molecular and cell biology, HLA-DQ3 (DQ3) is a broad serotype category with split antigens HLA-DQ7, DQ8, and DQ9. Historically, originally recognized as MB3[1] a DC4 serotype, DQw3 was one of three early determined antigens recognized as HLA-DQ along with HLA-DQ1 and HLA-DQ2.[2] While the DQ3 molecules are structurally similar in beta chain, the DQ molecules differ markedly in function, even when present with the same DQ alpha subunit. For this reason they are best treated independently.

Serology

DQ3, DQ7, DQ8, and DQ9 recognition of Some DRB1*and [3]
DQB1* DQ7 DQ3 DQ8 Sample
allele % % % size (N)
0301 85 40 1 12220
0304 40 35 8 111
.
DQ8 DQ3 DQ7 N
0302 66 25 1 6657
0305 34 30 70
DQ9 DQ3 DQ2 N
0303 67 12 11
DQ7 DQ8 N
0303 1 1 2563

The serotyping efficiency of DQ3 recognition relative to DQ2, DQ7, DQ8, and DQ9 is shown to the left. Compared to DQ2 serotyping of DQB1*0201 positive individuals (98%), the efficiency of DQ3 recognition is relatively low and error prone. This compares to genotyping efficiency of 100%. The recognition of DQB1*0303 by DQ9 and or DQ3 is poorest, DQ2 which recognizes a different DBB1*group recognizes DQB1*0303 as efficiently as DQ3.

For this reason DQ3 serotyping is a poor method of typing for transplantation or disease association prediction or study. Nonetheless, it is still widely used and association purported in the literature.

Alleles

DQB1*0301

DQB1*0301 the DQ7 gene, is detailed on HLA-DQ7

DQB1*0302

DQB1*0302 the DQ8 gene, is detailed on HLA-DQ8

DQB1*0303

DQB1*0303 the DQ9 gene, is detailed on HLA-DQ9

DQB1*0304

DQB1*0304 is similar in structure and function to DQB1*0301 generally considered to be HLA-DQ7

DQB1*0305

DQB1*0305 is similar in structure and function to DQB1*0302 generally considered to be HLA-DQ8

References

  1. "Further characterization of HLA-DS molecules: implications for studies assessing the role of human Ia molecules in cell interactions and disease susceptibility". Proc. Natl. Acad. Sci. U.S.A. 80 (18): 5719–23. 1983. doi:10.1073/pnas.80.18.5719. PMID 6193521. 
  2. "Implication of structural class II gene polymorphism for the concept of serologic specificities". Immunol. Rev. 85: 107–28. 1985. doi:10.1111/j.1600-065X.1985.tb01132.x. PMID 2412948. 
  3. derived from IMGT/HLA