Identification of two new HLA-B22 variants, HLA-B*5509 and B*5606

In our recent study using high-resolution HLA-B locus typing by sequence-ba sed typing (SBT) we identified 9 new alleles in a total of 355 unrelated in dividuals (4). Three of them concerned an allele belonging to the B22 group . One of them, B*5607, showed the unusual presence of a Bw4 sequence motif, as described previously (5). In this report the other two B22 variants are described; one belonging to the B55 specificity and named B*5509; the othe r one being a B*56 allele and assigned B*5606, which brings the total numbe r of alleles belonging to the B22 group to 18.