The single DR ? gene of the DRw8 haplotype is closely related to the DR ? 3III gene encoding DRw52

Abstract

In most individuals two HLA-DR _β genes are expressed from each chromosome. One of these genes encodes one of the classical DR specificities, while the other encodes either of the supertypic DRw52/DRw53 specificities. In addition to these genes usually one or two DR _β pseudogenes are present. In contrast, the DRw8 chromosomal region only contains a single DR _β gene. To determine the relationship of this single gene to the multiple DR _β genes of other DR specificities, comparisons of Southern genomic blots were carried out. In this analysis genomic clones for each individual DR _β chain locus were included. The DR _β w8 gene was indistinguishable from the DR _β III gene of DR3 cells (encoding DRw52), suggesting that it is closely related to the latter gene. The functional implications of this finding are discussed.