Genotype Frequencies of Platelet Glycoprotein IIIa-Specific Antigens and Granulocyte Antigens In Korean Pregnant Women* / 대한수혈학회지

ABSTRACT

BACKROUND: Polymorphism of glycoprotein IIIa on human platelets is one of the factors in alloimmunization that causes neonatal alloimmune thrombocytopenia (NATP), and the granulocyte antigens NA1 and NA2 are often targets of granulocytes antibodies causing neonatal alloimmune neutropenia (NANP). Currently, serotyping relies on the properties of the typing sera or antibodies and technique used. Genotyping circumvents the problems associated with serotyping. METHODS: The genomic DNA of 200 unrelated pregnant women admitted to Taegu Fatima Hospital was typed for three platelet glycoprotein IIIa-specific antigens (HPA-1, HPA-4, and HPA-6w) and granulocyte antigens (NA1 and NA2). Allele specific amplification test using primer designed to study HPA-1 and HPA-4, restriction fragment length polymorphism to study HPA-6w, and sequence specific primers for NA1 and NA2 were used for genotyping. RESULTS: The genotype frequencies were HPA-1(a+b-) 100%, HPA-4 (a+b-) 97.5%, HPA-4(a+b+) 2.5%, HPA-6w(a+b-) 97%, and HPA-6w(a+b+) 3%. These frequencies are similar to Japanese but different from Caucasian. The gene frequencies of NA1 and NA2 were 0.56 and 0.44 respectively. There are no cases of alloimmune thrombocytopenia and neutropenia in newborns from the 200 studied women. CONCLUSIONS: The differences in genotype frequencies among platelet glycoprotein IIIa-specific antigens and in the gene frequencies of NA in Koreans are shown as compared with other ethnic groups. Therefore it is needed to find the proper screening target antigens and antibodies for Korean NATP and NANP patients.