Comparison of multiple HLA-A alleles at the DNA level by using southern blotting and HLA-A-specific probes

Numerous alleles of the HLA-A gene have been serologically identified. In this report we present a rapid and straightforward means to assess HLA-A polymorphism at the genomic level. Using 5' and 3' HLA-A-specific DNA probes and Southern blotting, we have placed the recognition sequences for five endonucleases relative to the coding regions of 15 HLA-A alleles. These data permit two interesting conclusions: 1) four of the HLA-A alleles studied are associated with unique restriction fragments, and 2) HLA-A alleles of a cross-reactive group are more closely related at the DNA level than are noncross-reactive alleles.