Identification of a new HLA-Cw*05 allele, HLA-Cw*0505*.

We have identified a new human leukocyte antigen-C allele in a Caucasian potential stem-cell donor. The new allele is identical to the other Cw*05 alleles in exon 2 but differs from Cw*0501 and *0503 at nucleotide position 379 in exon 3, where a C is substituted with a G. This results in an amino acid substitution from leucine to valine at residue 103 in alpha2 helix.

Identification of a new HLA-DPB1 allele,HLA-DPB1*9001.

During routine typing of a potential bone marrow donor, a new HLA DPB1 allele was identified. The new allele, officially named HLA DPB1*9001, differs from HLA DPB1*01011 in the second hypervariable region, where a single nucleotide substitution in position 191 changes the codon 35 from TAC to TTC with a predicted amino acid change from Tyr to Phe.

Two new HLA Cw* alleles, Cw*0105 and Cw*1405, detected by sequence based typing.

During recent years, the view of the relative importance of the HLA Cw locus has undergone substantial change. From being an HLA locus with both limited polymorphism and biological significance there are now more than a hundred different alleles known and the biological importance of HLA Cw, both as a transplantation antigen and as a receptor for NK cells, is well established. Sequence based typing has been shown to be a powerful tool, especially for HLA Cw typing. Here we describe two new HLA Cw* alleles found during routine typing of potential bone marrow donors and hematological patients. The HLA Cw*0105 differs from Cw*0102 at positions 361 and 368 in exon 3 leading to a Trp to Arg and Cys to Ser substitution, respectively. HLA Cw*1405 differs from Cw*14021 by a single nucleotide substitution at position 368. This mutation results in an amino acid substitution of Phe for Tyr.

Identification of a novel HLA DRB1 exon 2 sequence, DRB1*1345.

Five different haplotypes in the human HLA D region are recognized based on their gene composition. The HLA DR52 associated DRB1 alleles include DRB1*03/08/11/12/13/14 and are characterized by the YST sequence motif in the codons 10-12 but vary in other polymorphic regions. The mechanisms generating the extensive variability are not entirely clear. Some alleles have probably arisen from point mutations, but most polymorphism has probably been caused by intralocus gene conversion, and the distinction between the ancient serologically defined groups is more and more difficult. This report describes the identification of a novel DRB1* allele - DRB1*1345 - found in a kidney transplant recipient from East Africa. The new allele shows the closest resemblance to DRB1*1114 and DRB1*1323. It differs from both those alleles at codons 57, 58 and 60, where the new allele carries the 'A-H' sequence motif common to DRB1*14 alleles such as 1401/04/07/10/16/25. This motif is only found in one other DRB1*13 allele namely DRB1*1343.