Determination of DR beta 1 alleles of DR4/Dw subtypes by oligonucleotide probing

The extensive Dw polymorphism of HLA-D has, to date, been defined using cumbersome and lengthy techniques involving T-cell proliferative reactions. These techniques have not necessarily provided information about the genotype at any single locus of HLA-D because the products of more than a single locus of HLA-D (e.g., DR beta 1 and DR beta 2 of the DR2 haplotypes and in some cases DQ) can contribute to T-cell proliferation and thus to assignment of Dw phenotype. We have recently reported that DR beta 1 alleles relating to the Dw polymorphism can vary by only a single, or a very few, nucleotide differences; the products of this locus are recognized in allo- and restricted responses. Given the importance of defining this polymorphism, we have used specific oligonucleotides as hybridization probes to differentiate between these very closely related alleles. This approach provides the basis for a rapid method for HLA-D typing which, as additional sequence information becomes available, will likely be generally applicable. In addition, oligonucleotide probing allows definition of a gene transcript from an individual locus of HLA-D rather than the phenotype results provided by Dw typing.