HLA-DQ6

Serology

Alleles

DQB1*0601

DQB10601 is generally linked to DQA10103 as 6.1 haplotype. This haplotype is more common in Japan and other parts of East Asia.

DQB1*0602

DQB10602 is commonly linked to DQA10102 to form 6.2 haplotype. DQ6.2 and is common from Central Asia into Western Europe, 0602 is also linked to DQA10103 in parts of Asia.

DQB1*0603

DQB10603 is commonly linked to DQA10103 as 6.3 and is common from Central Asia into Western Europe, 0603 is also linked to DQA10102 in parts of Asia. In Europe it is most common in the Netherlands.

DQB1*0604

DQB10604 is found at higher frequencies in parts Africa and Asia and is linked almost exclusively to DQA10102 as 6.4. This haplotype is found at its highest Eurasian frequencies in Japan.

DQB1*0609

DQB1*0609 is found in Africa and proximal regions of Eurasia.

Haplotypes and disease

Susceptibility to Leptospirosis infection was found associated with undifferentiated DQ6. Whereas DQ6 was protective against death (or need for liver transplantion) in primary sclerosing cholangitis.

DQ6.1

DQA10103:DQB10601 (DQ6.1) is found at increased frequencies in Asia and is almost absent in Western Europe. It confers protection from narcolepsy, juvenile diabetes, Vogt-Koyanagi-Harada (VKH) syndrome, pemphigus vulgaris, multiple sclerosis, myasthenia gravis.

DQ6.2

DQ6.2 (DQA1 : DQB1) 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 DQ6.2. DQA1 increases risk cervical cancer. In multiple sclerosis DQA1 was the most frequent allele and DQB1 increased significantly in the MS patients.

Protective effects of DQ6.2

In primary biliary cirrhosis DQ6.2 appears to have a negative association with disease. DQ6.2 also appears to have a protective effect in juvenile diabetes. DQ6.2 is also protective against infantile spasms in mestizos.

DQ6.3

DQ6.3 (DQA1 : DQB1) is found in northcentral Europe at moderate frequencies, it is a protective against many autoimmune diseases. It also affords some protection to HIV infection.

DQ6.4

DQ6.4 (DQA1 : DQB1) might be associated with thymoma-induced myasthenia gravis.

References

References

1. [http://www.ebi.ac.uk/imgt/hla/allele.html Allele Query Form] [[HLA Informatics Group. IMGT/HLA]] - [[European Bioinformatics Institute]]
2. (2003). "New allele frequency database". Tissue Antigens.
3. Lingappa J. (May 2004). "HLA-DQ6 and ingestion of contaminated water: possible gene-environment interaction in an outbreak of Leptospirosis". Genes Immun..
4. Boberg KM. (August 2001). "The HLA-DR3,DQ2 heterozygous genotype is associated with an accelerated progression of primary sclerosing cholangitis". Scand. J. Gastroenterol..
5. Hong SC. (2007). "DQB10301 and DQB10601 modulate narcolepsy susceptibility in Koreans". Hum. Immunol..
6. (2001). "Relationship between HLA-DRB1 and DQ alleles and the genetic susceptibility to type 1 diabetes". Chin. Med. J..
7. Saruhan-Direskeneli G. (2000). "HLA-DR and -DQ associations with insulin-dependent diabetes mellitus in a population of Turkey". Hum. Immunol..
8. Kim MH. (2000). "Association of HLA with Vogt-Koyanagi-Harada syndrome in Koreans". Am. J. Ophthalmol..
9. Niizeki H. (1994). "HLA-DQA1, -DQB1 and -DRB1 genotyping in Japanese pemphigus vulgaris patients by the PCR-RFLP method". Tissue Antigens.
10. Amirzargar A. (1998). "HLA class II (DRB1, DQA1 and DQB1) associated genetic susceptibility in Iranian multiple sclerosis (MS) patients". Eur. J. Immunogenet..
11. (2006). "Subtle differences in HLA DQ haplotype-associated presentation of AChR alpha-chain peptides may suffice to mediate myasthenia gravis". Autoimmunity.
12. Ghaderi M. (October 2000). "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". Cancer Epidemiol. Biomarkers Prev..
13. (2005). "HLA alleles and risk of cervical intraepithelial neoplasia among southwestern American Indian women". Hum. Immunol..
14. (May 1989). "Multiple sclerosis patients have a high frequency of an HLA-DQ beta epitope defined by a human-human hybridoma antibody". Tissue Antigens.
15. Amirzargar AA. (2005). "Optic neuritis, multiple sclerosis and human leukocyte antigen: results of a 4-year follow-up study". Eur. J. Neurol..
16. Fernández O. (2004). "DQB1*0602 allele shows a strong association with multiple sclerosis in patients in Malaga, Spain". J. Neurol..
17. Mullarkey ME. (2005). "Human leukocyte antigen class II alleles in Caucasian women with primary biliary cirrhosis". Tissue Antigens.
18. (March 2002). "Sequencing of the second exon of the MHC class II DQ6 alleles in patients with type 1 diabetes". Autoimmunity.
19. (August 2002). "Genetics of type 1 diabetes mellitus". Genes Immun..
20. (February 2001). "Contribution of the MHC class II antigens to the etiology of infantile spasm in Mexican Mestizos". Epilepsia.
21. (1996). "HIV-1 disease association with HLA-DQ antigens in African Americans and Caucasians". Pathobiology.
22. (1993). "Identification by genomic typing of non-DR3 HLA class II genes associated with myasthenia gravis". J Neuroimmunol.