Oligonucleotide genotyping shows that alleles at the HLA-DR ? III locus of the DRw52 supertypic group segregate independently of known DR or Dw specificities

Abstract

Using locus- and allele-specific oligonucleotide probes, we have studied the polymorphism of the HLA-DR _β III locus within the haplotypes of the DRw52 supertypic group. DNA from a number of homozygous typing cells typed for both Dw and DR was used. The DR _β III polymorphisms, DRw52a and DRw52b, do not segregate with Dw typing, or with DR typing, indicating that the determinants responsible for Dw-defined T -cell response and for DR haplotypic recognition are not encoded by the DR _β III locus. Hence, we can conclude that these DR specificities are encoded by the other functional DR locus, DR _β I, while the DR _β III locus encodes only the supertypic product.