Abstract: | The human major histocompatibility complex class II antigens of the HLA-D are highly polymorphic, surface proteins essential in the cellular interactions necessary for an immune response. The analysis of this polymorphism is crucial for (i) histocompatibility matching for transplantation and (ii) understanding the association between HLA-D and certain important diseases. The polymorphism of certain HLA-D haplotypes may escape detection by current methodologies. Analysis at the genomic level of the polymorphism of one of the HLA-D subregions HLA-DR, using oligonucleotide probes specific for the polymorphic regions, is capable of distinguishing single nucleotide differences. The DRw6 haplotype was analyzed in view of the lack of DRw6 specific sera. On the basis of nucleotide sequence analysis, the DRw6 haplotype consists of at least two subtypes. When analyzed with oligonucleotide probes, this split identifies new polymorphic groups that differ from the DRw6 serological subgroups. |