A DPB1 typing method is described that assigns DPB1 alleles into six groups based on polymorphism at amino acid positions 8-9 and 84-87 using sequence-specific priming (SSP). The results obtained allow the selection of primers for a subsequent sequence-specific oligonucleotide (SSO) hybridization procedure which permits DPB1 alleles to be analysed separately in a heterozygote individual. This has greatly reduced the occurrence of typing reaction patterns consistent with multiple combinations of DPB1 alleles seen in other DPB1 typing methods.