Several methods for low-resolution class I typing of potential bone marrow
donors are available. The National Marrow Donor Program(R) (NMDP) has initi
ated pilot projects for large-scale DNA-based class I typing to initially c
haracterize donors. Sequence-specific oligonucleotide probe hybridization a
nd sequence-specific primer polymerase chain reaction (PCR) screening of 3,
500 NMDP potential donors suggested the presence of variants of known HLA-B
*15 variants in 3 donors. PCR products encompassing HLA-B locus exons 1 thr
ough 3 were prepared and subcloned. Sequencing revealed 3 alleles differing
from known HLA-B*15 alleles by nucleotide substitutions resulting in predi
cted novel HLA-B antigens. The new alleles occur in distinct ethnic groups.
These findings further illustrate the substantial genetic variation presen
t at the HLA-B locus within human populations.