A new allele, HLA-B*1555, identified in an African patient awaiting bone marrow transplantation

Human HLA genes exhibit extreme polymorphism, the extent of which is emphas ised by the identification of an ever increasing number of new alleles by D NA-based typing strategies. Here we describe a novel allele, belonging to t he HLA-B*15 group, which was idenified in an African patient awaiting a bon e marrow transplant. This individual was shown to exhibit two HLA-B alleles , B*5301 and a new allele which has been named B*1555. B*1555 differs from B*1531 in exon 3 by a single nucleotide substitution. This substitution res ults in a change in the amino acid residue at position 97, which is located within the beta-pleated sheet region of the HLA molecule.