DNA typing for class II hla antigens with allele-specific or group-specific amplification. II. typing for alleles of the DRw52-associated group

Codons 9-12 of the first domain of DRB1, which encode the amino acid sequence EYST (in single-letter code), served as the basis for the construction of a polymerase chain reaction primer specific for DRB1 of the whole DRw52 group. Using this primer for the 5' end and a primer for a conserved region at the 3' end, we could amplify selectively the DRB1 genes of DRw17-, w18-, w11-, w13-, w14, and w8-positive haplotypes. DRB3 genes of DR3,DR5 and DRw6 were also specifically amplified, separately. This selectively amplified DNA could then be used in a blotting procedure for hybridization with oligonucleotide probes chosen to define the polymorphisms that characterize these alleles and their subsets. Patterns of hybridization for groups of related specificities have been described, and their frequencies were determined in representative panels available in our laboratory. The results presented illustrates the extraordinary power of this new DNA typing procedure. Using these relatively simple methods it is possible to define, with certainty, allelic forms of DRB1 and DRB3 associated with the DRw52 group. The ability to type extends far beyond the capabilities of present serology; the precision achieved with this method in panel typings is unprecedented.