Blood groups and their importance in the mammals
The article gives an overview achievements in immunogenetics and their application in medicine and livestock practices. The data on the various functions of blood group antigens, mechanisms of their formation, the importance of blood groups in the medical and agricultural practices, their connection with the hosts-tively-useful sings of animals and disease resistance. The purpose of the study-summarize the achievements of immunogenetics and identify opportunities for their further use in the practice of animal breeding. For a long time, erythrocytes were considered as inert cells-containers filled with hemoglobin and intended only for the delivery of oxygen to the tissues of the body. However, the studies led to a deeper understanding of the functions of the blood groups in the body and the mechanisms of their formation. The functions of the erythrocyte are not limited only to the delivery of oxygen to the tissues of the body, its outer shell carries a huge number of molecules, the set of which is genetically predetermined and they perform a variety of functions in the body. Moreover, the set of such molecules in different people and animals varies due to the great genetic diversity, both human population and animal populations. The ones that define blood groups are called antigens of blood groups. Most often, such antigens are present only on red blood cells, but there are those that are found on lymphocytes and even in non-rove tissue: liver, kidney, heart, sperm and even in body fluids, and their role in the body is unclarified. A number of these protein antigens serve as transmembrane transporters (for example, the Diego system in human body), transferring water molecules, HCO3 anions, urea, etc. through the erythrocyte membrane. The other part of blood group antigens located on lymphocytes and in a soluble form in body fluids perform protective functions in the body. Some antigens (in humans - the Cromer system, in cattle - EAN-system, in pigs - AO system) serve as receptors for physiological substances, as well as for pathogenic microflora. Many antigens of blood groups perform structural functions in the body (in humans, the antigens of the MHS system). Another series of antigens is molecules of intercellular interactions. In addition, the antigens of a number of blood group loci, together with a complex of genes of other protein loci, participate in the formation of economically-useful signs and the stability or predisposition of an organism to diseases. It is the set of different functions that the antigens of blood groups perform in the body that explain their striking diversity in humans - among different peoples, in animals - among different species, breeds and populations.