PLATELET ALLOANTIGENS HPA-1, HPA-2, HPA-3, HPA-5 AND HPA-6B IN FINNS

The human platelet alloantigens HPA-1, -2, -3, -5 and -6b in the Finnish population were determined using allele specific restriction analysis (PCR-ASRA) for HPA-1, -2, -3 and -5 and monoclonal antibody immobilized platelet antigen (MAIPA) assay for HPA-1, -3a, -5b and -6b. No discrepancies were observed between the results obtained with the PCR-method and those obtained serologically. The gene frequencies obtained from 200 unrelated Finns were 0.86 and 0.14 for HPA-1a and -1b, 0.91 and 0.09 for HPA-2a and -2b, 0.59 and 0.41 for HPA-3a and -3b and 0.95 and 0.05 for HPA-5a and -5b. The frequency of the HPA-Sb allele (10%) is lower in Finns than in Central- or South-European populations (20-30%). The HPA-1, -2 and -3 frequencies did not deviate from those observed in other European populations. The rare HPA-6b antigen was observed in three of 127 individuals from south-eastern Finland (2.4%), which suggests that the frequency of this allele in Finland is higher than previously thought.