title: A systematic study of HLA class II-beta DNA restriction fragments in insulin-dependent diabetes mellitus.
abstract: DNA restriction fragments of the genes encoding HLA class II-beta antigens were compared in 34 patients with insulin-dependent diabetes mellitus and 34 HLA-DR-matched healthy individuals. Ninety-three fragments, determined by six restriction enzymes (EcoRI, EcoRV, HindIII, BamHI, Pvu II, and Taq I), were analyzed: (i) A DR Taq I 12.7-kilobase-pair fragment might be a marker for the extended haplotype HLA-B8, DR3. (ii) In controls, DR4 haplotypes are associated with two distinct clusters of DQ restriction fragments (DQR4 and DQR5). Almost all (94%) DR4 patients belong to the DQR4 and not to the DQR5 cluster. This suggests that, among HLA-DR4 haplotypes, only DQR4 haplotypes are involved in susceptibility to insulin-dependent diabetes mellitus. (iii) A DR Taq I 14.5-kilobase-pair fragment was found to be strongly associated with DQR4, mainly in DR3/DR4 heterozygous patients (P = 5 X 10(-4). However, these results must be interpreted with caution, taking into account the high number of statistical tests performed.
authors.forename: O
authors.initials: O
authors.lastname: Cohen-Haguenauer
authors.forename: E
authors.initials: E
authors.lastname: Robbins
authors.forename: C
authors.initials: C
authors.lastname: Massart
authors.forename: M
authors.initials: M
authors.lastname: Busson
authors.forename: I
authors.initials: I
authors.lastname: Deschamps
authors.forename: J
authors.initials: J
authors.lastname: Hors
authors.forename: J M
authors.initials: JM
authors.lastname: Lalouel
authors.forename: J
authors.initials: J
authors.lastname: Dausset
authors.forename: D
authors.initials: D
authors.lastname: Cohen
mesh_terms: D004262:DNA Restriction Enzymes; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics* / Q000276:immunology; D005796:Genes; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D006801:Humans; D011110:Polymorphism, Genetic; D013223:Statistics as Topic
chemical_list: D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II; D004262:DNA Restriction Enzymes