title: HLA-DR and -DQ genotypes of celiac disease patients serologically typed to be non-DR3 or non-DR5/7.
abstract: The susceptibility to develop celiac disease (CD) seems to be primarily associated to a particular HLA-DQ alpha/beta heterodimer encoded by the DQA1*0501 and DQB1*0201 alleles, in cis position on the DR3-DQ2 haplotype or in trans position by DR5-DQ7/DR7-DQ2 heterozygotes. However, exceptional patients exist who are neither DR3 nor DR5/DR7, particularly among Southern European populations. We therefore examined the DRB1, DQA1, and DQB1 alleles of 13 Spanish CD patients who were serologically typed to be neither DR3 nor DR5/DR7. Five patients were found to carry the DQA1*0501 and DQB1*0201 alleles either in cis or in trans position, three of them had previously been serologically mistyped. However, two of these patients carried DQA1*0501 and DQB1*0201 on haplotypes other than DR3 or DR5 in combination with DR7. One of the latter patients carried an unusual DR4-DQ2 haplotype, while another had an unusual DR8-DQ2 haplotype. Four of the remaining eight patients carried DR4-DQ8 haplotypes. Taken together, our findings provide further evidence that the DQ alpha/beta heterodimer encoded by the DQA1*0501 and the DQB1*0201 alleles confers the primary HLA-associated susceptibility to develop CD. However, our studies also corroborate that a second (and "weaker") HLA-associated CD susceptibility gene may be present on some DR4-carrying haplotypes.
authors.affiliation: Institute of Transplantation Immunology, National Hospital, Oslo, Norway.
authors.forename: A
authors.initials: A
authors.lastname: Spurkland
authors.forename: L M
authors.initials: LM
authors.lastname: Sollid
authors.forename: I
authors.initials: I
authors.lastname: Polanco
authors.forename: F
authors.initials: F
authors.lastname: Vartdal
authors.forename: E
authors.initials: E
authors.lastname: Thorsby
mesh_terms: D000293:Adolescent; D000328:Adult; D002446:Celiac Disease / Q000276:immunology*; D002648:Child; D004198:Disease Susceptibility; D005260:Female; D006683:HLA-DQ Antigens / Q000032:analysis*; D006684:HLA-DR Antigens / Q000032:analysis*; D006239:Haplotypes; D006801:Humans; D016130:Immunophenotyping; D008297:Male; D015345:Oligonucleotide Probes; D013030:Spain
chemical_list: D006683:HLA-DQ Antigens; D006684:HLA-DR Antigens; D015345:Oligonucleotide Probes