ABO血液型の抗原および遺伝子の解析と臨床的応用

The ABO blood group system is the most important blood group system among the 29 International Society of Blood Transfusion（ISBT）-recognized systems, consisting of four antigens （A, B, O, and AB）. These antigens are known as oligosaccharide antigens, and widely expressed on the membrane of red cell and tissue cells as well as, in the saliva and body fluid. The ABO blood group system was discovered by the Austrian scientist Karl Landsteiner, who found three different blood types（A, B, and O）in 1900 from serological differences in blood. In 1902, DeCasterllo and Stürli discovered the fourth type, AB. The phenomenon of these serological differences was called the Landsteiner Law, and is still used to detect ABO blood group antigens in clinical laboratories. In 1924, Felix Bernstein predicted that the mechanism of inheritance involved three alleles at the ABO locus from extensive family studies. Furthermore, the structure and biochemical characteristics of the ABO antigens were elucidated by many investigators. In recent years, the ABO blood group at chromosome locus 9 has been determined, the gene cloned and the structures determined by Yamamoto et al . This has made it possible to genetically analyses of ABO blood group antigens using molecular biology techniques. Clinically, blood group antigens are important. In particular, the ABO blood group antigens are one of the most important issues in transfusion medicine, evaluation of the adaptability of donor blood cells with bone marrow transplantations, and survival confirmation of hemocytes. This article reviews the serology, biochemistry, biosynthesis and genetic characteristics of ABO antigens, and the analysis of ABO blood group using flow cytometry and polymerase chain reaction（PCR）amplification of specific alleles（PASA）-method and their application for clinical studies.