One of the different groups into which human blood is classified.
Classification of blood, based on the presence or absence of certain antigens on the surface of red blood cells (erythrocytes), used to determine compatibility for transfusions. There are many systems for classifying blood; the most commonly used is the ABO blood group system.
A system that classifies blood by the proteins contained in its red blood cells; also known as blood types. Blood group is important in determining the safety of blood transfusions. If blood from one blood group is transfused into a person with a different blood group, antibodies in the recipient’s blood will attack the donated blood as a foreign substance. Transfusions between people of the same blood group are almost always successful.
Any one of the many types into which a person’s blood may be classified, based on the presence or absence of certain inherited antigens on the surface of the red blood cells. Blood of one group contains antibodies in the serum that react against the cells of other groups.
People are divided into four main groups in respect of a certain reaction of the blood. This depends upon the ability of the serum of one person’s blood to cause the red cells of another’s to stick together (agglutinate). The reaction depends on antigens, known as agglutinogens, in the erythrocytes and on antibodies, known as agglutinins, in the serum. There are two of each, the agglutinogens being known as A and B. A person’s erythrocytes may have (1) no agglutinogens, (2) agglutinogen A, (3) agglutinogen B, (4) agglutinogens A and B; these are the four groups. Since the identification of the ABO and Rhesus factors, around 400 other antigens have been discovered, but they cause few problems over transfusions.
A genetically determined system of antigens located on the surface of the erythrocyte. There are a number human blood group systems; each system is determined by a series of two or more genes that are allelic or closely linked on a single autosomal chromosome. The ABO system (discovered in 1901 by Karl Landsteiner) is of prime importance in blood transfusions. The Rhesus (Rh) system is especially important in obstetrics. There are bout 30 Rh antigens.
A classification of blood based on whether certain proteins are present on the surface of the red blood cells; blood type.
There are established systems for categorizing blood based on the distinct antigens (marker proteins) present on the surface of red blood cells (RBCs) and the corresponding antibodies found in the blood plasma. These antigens play a crucial role in determining the RBCs’ ability to trigger an immune response. The two primary blood grouping systems employed are the ABO system and the rhesus system.
In this particular classification system, an individual’s blood group is determined by the presence or absence of two types of antigens, namely A and B, on the surface of their red blood cells (RBCs). Individuals with the A antigen belong to blood group A and possess anti-B antibodies. Those with the B antigen fall into blood group B and have anti-A antibodies. Individuals with both antigens are classified as blood group AB and do not have either type of antibody. On the other hand, individuals without either antigen are categorized as blood group O and possess both types of antibodies.
The rhesus system encompasses multiple antigens, with the key antigen known as factor D. Individuals who possess this factor are classified as Rh-positive, while those who lack it are categorized as Rh-negative. The significance of the Rh group primarily pertains to pregnancy in Rh-negative women. If the baby is Rh-positive, the mother may develop antibodies against the baby’s blood, making it a crucial consideration in prenatal care.
Accurate blood group typing is vital to ensure the safety of blood transfusions. The ABO and rhesus groups are employed to classify blood units stored in blood banks. This classification enables the selection of donor blood that is compatible with the recipient’s blood type before the transfusion procedure. By matching the blood groups, the risk of adverse reactions during transfusion is minimized, promoting a safer and more successful transfusion process.
The inheritance of a person’s blood group makes it useful in paternity testing. By examining the blood group, it becomes possible to determine familial relationships and establish paternity. Furthermore, genetic analysis can provide a high level of certainty in identifying the blood of a criminal suspect. This analysis serves as a powerful tool in forensic investigations, allowing for accurate identification and linking of individuals to crime scenes with virtual certainty.