DPB1*8601, a previously unrecognized DPB1 variant in the Caucasoid population.

A new, previously unrecognized DPB1* allele, DPB1*8601, was found in a Swedish family. The new allele was carried on the common North European haplotype HLA A1-B8-DR3. Both individuals carrying the new allele were initially typed as clear DPB1*4601,*6601 but after family studies and further typing with allele-specific primers it was concluded that a new allele was present together with the common DPB1*0401. The new allele was investigated by direct sequencing of exon 2 in both forward and reverse directions employing intron primers combined with either an allele-specific sense or anti-sense biotinylated primer for bi-directional sequencing. The new allele is identical to DPB1*1701 in the five first variable regions. In the sixth region, however, DPB1*8601 carries the GGPM motif shared by several common alleles such as DPB1*0201 and 0401and 0402.