Gene frequencies of the HPA-1 to HPA-13, Oe and Gov platelet antigen alleles in Taiwanese, Indonesian, Filipino and Thai populations.

Human platelet antigen (HPA) systems consist of more than twelve bi-allelic antigen polymorphisms in which a base pair substitution leads to change in an amino acid of a glycoprotein expressed on the platelet. The neonatal alloimmune thrombocytopenia (NAIT), post transfusion purpura, and refractoriness to platelet transfusion can be induced by antibodies against human platelet antigens: e.g. HPA-1a, 3a, 4a, 5a, and Gova. HPA typing is essential for the diagnosis and treatment of a variety of diseases. We developed a PCR-based method to detect HPA-1 to HPA-13, Oe and Gov platelet alloantigens. In this method, the amplified PCR products were used to recognize the polymorphism after restriction enzyme digestions. Among 566 Taiwanese, 107 Indonesian, 100 Filipino and 137 Thai subjects studied, HPA-1a, 2a, 4a, 5a, 6a, 7aW, 8aW, 9a, 10a, 11a, 12a, 13a, Oea genes were present in every sample; while HPA-1b, 2b, 4b, 5b and 6b were rarely found. HPA-7aW, 8aW, 9, 10, 11, 12, 13, and Oea alleles were noted to be monomorphic only. HPA-3a/3b alleles had frequencies of 0.595/0.405, 0.505/0.495, 0.507/0.493, 0.530/0.470, while Gova/Govb of 0.462/0.538, 0.450/0.550, 0.463/0.537, 0.520/0.480 among Taiwanese, Indonesians, Thais and Filipinos respectively. The prevalence rates of HPA-1 to 13 in this study were also consistent with other previous reports using different methods. The alloimmunization due to Gov and HPA-3 antigens need to be emphasized in these populations.