Blood Group - one of the individual genetically determined traits of the human body. It is determined at birth and is not subject to change. It is conventional ABO and Rh (rhesus). The most common blood type makes life easier for its owner. The more rare is, the harder it is to choose the donor and the longer this process, even with the development of transfusion service, this problem still is acute.
What is the most common blood type
ABO system - system antigens (agglutinogens) and their antibodies (agglutinins). Agglutinogens - antigens A, B, arranged on the outer surface of the erythrocyte membrane. They are encoded by genes A (encodes an antigen A), B (encodes an antigen B), O (encodes the absence of antigen).
Agglutinins - antibodies a, b, which are located in the plasma. According to the structure they are proteins that belong to the class of immunoglobulins, representing a component of the immune system. The children of the first months of life due to immaturity of the immune system are missing. Gradually produced during the growth and development of the child, reaching adult levels by 10-15 years.
Upon binding of antigen A with agglutinin and agglutination - precipitation of erythrocytes. Similarly, the interaction of B and b. Therefore, a group of human blood contains heteronymic agglutinogens and agglutinins.
ABO system is represented by 4 groups:
- First - it does not contain antigens, but present both types of antibodies - a and b.
- Second - can be encoded by genes AA and AO gene contains antigen A on the red blood cells and agglutinin b in the plasma.
- Third - may be encoded by genes BB and B0 contains an antigen in erythrocytes and in plasma and agglutinin.
- Fourth - encoded genes A and B contains antigens A and B, is not a part of agglutinins.
Previously, transfusion circuit existed between groups. In peacetime, the only single-group transfused blood, the concept of universal donors and recipients are outdated. Whole heme is transferred only in one situation - when Rh-conflict, or use your own whole blood taken from the cavities during surgery or received and logged by dilution.
But there are exceptions - people with blood group I may be a universal donor red blood cell (their red blood cells do not contain the antigen on their membrane), and People with group IV - universal plasma donors because their plasma does not contain anti-A and anti-B antibodies (provided that the Rh system and donor negative).
The frequency of the prevalence of blood groups correspond to their numbers. Distribution of blood there is no equivalent in the world. In each territory dominated by their genotype. The most popular on the planet is a group I - its owners account for approximately 55% of the population. The next most common - II, then - III, the most rare - IV. According to recent data, in Russia, the most common group 2.
It is believed that people with I group have the most highly resistant to physical stress and a strong immune system, the reverse side is that they often diagnosed atopic (allergic) disease - dermatitis, asthma, etc. Also, these individuals susceptible to diseases of the digestive system - gastritis, ulcers, cholecystitis.
People with group II gems more common coronary heart disease, joint disease, cancer, diabetes. In patients with I and II positive group there is less of a problem if needed transfusions - in the center of the blood supply such a large group.
The most common blood group - I and II are positive, and the rarest is the fourth negative. People with this genotype in the absence of infections and pathologies valued as donors.
What is Rh factor more common
Rhesus blood system - one of the groups represented by Rh antigen and antibodies to it. Rh protein is on the surface of red blood cells in rhesus-positive individuals, those with whom he is not, according to Rh-negative. Normally, antibodies to the Rh protein is not present, but if of Rh-negative person pour of Rh-positive blood or red blood cell (erythrocyte concentrate), then the immune system will react synthesized antirhesus antibodies. Repeated transfusions of Rh-positive blood agglutination occurs (curdle).
Inheritance Rh-antigen carried recessively-dominant - Rhesus positive dominant (suppresses) negative - recessive.
Rh antigen genes can be represented by C, D, E (dominant) and c, d, e - recessive. The presence of at least one dominant gene (CDE, CDe, Cde, cDE, cdE, cDe) indicates the presence of a rhesus protein on the membrane of the erythrocyte, i.e. Rh +. Rh negative is only found in individuals with recessive genotype - cde, which explains the low prevalence.
In a world of more than 80% of people are Rh-positive blood. Especially important is Rh-accessory for women - it is not only important in transfusion, but also for pregnancy planning. If a woman is pregnant Rh- blood Rh + fetus during delivery (or miscarriage, abortion) occurs immunization, and her immune system produces Rh agglutinins. Thus, if the next pregnancy the fetus will also be Rh +, the mother will reject it. To prevent mother Rhesus conflict during 1 pregnancy serum administered to Rh
Knowledge of statistics on groups of blood needed for donor services, obstetric care. Also, these data can indirectly judge the structure of morbidity in the country, to develop preventive measures noncommunicable conditions such as coronary heart disease, digestive system diseases, oncology.
