ANALYSIS OF HLA-A AND HLA-B SEROLOGIC TYPING OF BONE-MARROW REGISTRY DONORS USING POLYMERASE CHAIN-REACTION WITH SEQUENCE-SPECIFIC OLIGONUCLEOTIDE PROBES AND DNA-SEQUENCING

Unrelated volunteer donors (69) recruited by the National Marrow Donor Program were HLA typed by DNA-based methods for both the HLA-A and -B loci. Each donor had been previously typed by serology by at least tw o independent laboratories. Of the 69 samples, all serologic laborator ies were in concordance for HLA-A in 62 typed samples and for HLA-B in 48 typed samples. Of the serologically concordant samples, 5 samples typed for HLA-A and 7 samples typed for HLA-B received DNA and serolog y types differing in their level of resolution. One sample typed for H LA-A and 3 samples typed for HLA-B by DNA methods gave different resul ts from their serologic assignments. Of the samples exhibiting dispari ties among the different serologic typing laboratories, the DNA-define d types of 7 samples typed for HLA-A and 18 samples typed for HLA-B we re consistent with at least one of the serologic assignments. The DNA types for the remaining 3 HLA-B typed samples did not agree with the s erologic assignments and their alleles were subsequently sequenced. On e of these sequences was a previously undefined allele, B1537. Sharin g of polymorphic sequences among HLA allelic products creates difficul ties for consistent serologic assignments of some types complicating t he process of identifying potential donors from bone marrow registries . Thus, the use of DNA-based typing techniques for characterization of donor class I types should allow a more consistent definition of type s and should speed the donor selection process.