Veriryhmämäärityksiä

Veriryhmämäärityksiä, known in English as blood typing or blood group determination, refers to the laboratory tests used to identify the specific blood group of an individual. This classification is primarily based on the presence or absence of certain antigens on the surface of red blood cells and antibodies in the blood plasma. The most common blood typing system is the ABO system, which categorizes blood into four main groups: A, B, AB, and O. Group A has A antigens on red blood cells and anti-B antibodies in plasma. Group B has B antigens and anti-A antibodies. Group AB has both A and B antigens but no antibodies, while group O has neither A nor B antigens but both anti-A and anti-B antibodies.

Another crucial blood group system is the Rh system, which determines whether an individual is Rh-positive or Rh-negative based on the presence or absence of the Rh D antigen. Rh-positive individuals have the D antigen, while Rh-negative individuals do not. This distinction is particularly important during pregnancy and blood transfusions, as incompatibility can lead to serious immune reactions.

Blood typing is essential for several medical purposes. The most critical application is ensuring safe blood transfusions, as transfusing incompatible blood types can cause a severe and potentially fatal hemolytic transfusion reaction. It is also vital for prenatal care to prevent Rh incompatibility disease (hemolytic disease of the newborn) in cases where an Rh-negative mother carries an Rh-positive fetus. Furthermore, blood typing plays a role in forensic science for identification purposes and in anthropological studies to understand population genetics. The determination is typically performed by mixing a sample of the patient's red blood cells with specific antisera containing antibodies that react with known antigens. Agglutination, or clumping, indicates the presence of the corresponding antigen.