Genotyping of Human Platelet Antigens in Ethnic Northeastern Thais by the Polymerase Chain Reaction Sequence Specific Primer Technique
AMORNRAT V ROMPHRUK, M.Sc. *, PRAMOTE SRIV ANICHRAK, M.Sc. *, ARUNRAT ROMPHRUK, M.Sc.**, JONGKOL AKAHAT, M.Sc.*, CHINTANA PUAPAIROJ, M.D.*, CHANVIT LEELAYUWAT, Ph.D.**
Affiliation : *Blood Transfusion Centre, Faculty of Medicine, Khon Kaen University, **Department of Clinical Immunology and CMII-KKU Institutional Co-operative Centre, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, 40002, Thailand. Supported by a research grant from the Faculty of Medicine, Khon Kaen University, Thailand 1999 (No. II4-42-l ).
Human platelet antigens (HPA) are important in neonatal alloimmune thrombocytopenia (NAITP), post-transfusion purpura (PTP), refractoriness to platelet transfusion therapy and population genetics. Th_e distribution of HPA in a Northeast Thai population was studied. 300 healthy, unrelated, and ethnic Northeastern Thais were randomly selected. Using the polymerase chain reaction-sequence specific primer technique (PCR-SSP), the frequency of HPA-1, -2, -3, -4, -5 and -6 were determined. The phenotype frequencies were 100 per cent for HPA-la, 4a, 5a, and 6a. For HPA-lb, 2a, 2b, 3a, 3b, 5b and 6b, the frequencies were 5.7, 99.7, 12.3, 78.0, 71.3, 7.3 and 3.0 per cent, respectively. The HPA-4b was not found. The HPA frequencies in our sub- jects were quite similar to other Asian populations but were different from Caucasians. The distribution of HPA genotypes encountered in our study indicate that HPA-la, -4a, -4b, -5a and -6a will not be involved in NAITP, PTP and refractoriness to platelet transfusion therapy in North- eastern Thais. Moreover, HPA-lb, -2a, -2b, -3a, -3b, -5b and -6b may induce alloantibodies in these patients.
Keywords : Platelet Antigens, PCR-SSP
