Veriryhmien

Veriryhmien, or blood groups, are classifications of human blood based on the presence or absence of specific antigens on red blood cells and the corresponding antibodies in plasma. The most clinically important systems are ABO and Rh(D). In the ABO system, red cells carry A antigens, B antigens, both, or neither. Individuals with type A have A antigens and anti-B antibodies in plasma; type B has B antigens and anti-A antibodies; type AB has both antigens and no anti-A or anti-B antibodies; type O lacks A and B antigens and has both anti-A and anti-B antibodies.

Beyond ABO and Rh(D), many other blood group systems exist, including Kell, Duffy, Kidd, and MNS. These systems involve additional antigens on red cells and can influence transfusion outcomes, particularly in patients who receive repeated transfusions or in pregnancy where antigen compatibility matters.

Clinical transfusion practice emphasizes compatibility between donor and recipient blood. Serological typing identifies ABO and Rh(D) status, while crossmatching assesses potential reactions with donor plasma or cells. In pregnancy, Rh incompatibility between mother and fetus can lead to hemolytic disease of the newborn, a risk mitigated by prophylactic Rh(D) immune globulin in Rh-negative mothers.

Historically, the ABO system was described by Karl Landsteiner in 1900. The distribution of Veriryhmien varies among populations; Rh-negative individuals are more common in some groups than others. Understanding blood groups remains essential in transfusion medicine, transplantation, and related clinical and forensic contexts.