Wondering what blood groups are? Why do we have many types of blood group? Well, blood groups are complex chemical systems in blood cells, which differentiate a particular type from the other. Blood grouping is essential for various reasons including safe blood transfusion. Let us understand about blood groups, their types and the uses of blood group typing.
Blood Groups – Types And Uses Of Blood Group Typing
Blood groups and their types are a classification based on the presence or absence of certain chemicals in red blood cells. Here, we look at different blood groups, their types and the uses of blood group typing.
Types of Blood Groups
There are 4 types of blood groups: A, B, AB and O. This classification is based on the presence or absence of inherited antigenic substances on the surface of red blood cells (RBC).
The main blood grouping systems are the following
ABO group typing – The ABO blood grouping system is based on the two antigens and antibodies present in the blood. The antibodies present together with the antigens are
- Antigen A with antibody B
- Antigen B with antibody A
- Antigen AB has no antibodies
- Antigen nil (group O) with antibody A and B.
Rh group typing – This is the next most common blood grouping system, which determines the types of blood groups. The most important is D antigen which is absent in Rh negative individuals and can be produced in these individuals by sensitization only. The presence or absence of Rhesus antigen is denoted by + or – sign along with the A, B, AB or O blood groups.
What is Bombay Blood Group?
Bombay blood group was found first in Bombay (now known as Mumbai) and hence the name. This type of blood group is rare. These people can donate blood to the people with ABO blood groups but cannot receive from any blood group donor apart from Bombay blood group people. These people do not have antigen H in their blood but antibody H is present. It is also called as HH blood group. The cause for Bombay blood group is not clear but is surely one of the important types of blood groups.
Specific tests for detection of H antigen have to be conducted to classify as Bombay blood group. This blood group is often confused as O blood group because of lack of antigens.
What is Red Blood Cell Compatibility?
Red blood cell compatibility is important considering the health and safety of the person receiving a particular type of blood group. The red blood cell compatibility is seen among the various types of blood groups and is checked before blood transfusion to the recipient to avoid adverse reactions in recipient.
What Is Universal Donor?
Of all the types of blood groups, blood group O is universal donor, as these people can donate to any other blood groups. However, they can receive only from O blood group individuals as they do not have any antigens (A or B) on the surface of RBC.
What is Universal Recipient?
The blood group AB is universal recipient as these people can receive from any blood group. However, they cannot donate to others apart from AB blood group as they have both antigens (A and B) on the surface of RBC.
Uses Of Blood Group Typing
Blood group typing in done in specified labs in a specific manner. Collect the sample of blood in test tubes. Mix the blood with three different reagents including either of the three different antibodies, A, B or Rh antibodies and look for agglutination. Look into the each test tube and check if the test tube containing A antibody, B antibody or Rh antibody is agglutinated and determine the blood group accordingly. The agglutinations happen if the antibody matches the antigen present in the blood. The antigen and antibody bind in the lock and key model and hence the formation of agglutinations.
The uses of blood group typing are as follows
Blood Transfusions: This is one of the main uses of blood group typing. The blood group typing plays a major role here, as certain blood groups are compatible and some are not. If mismatched transfusion occurs it can lead to anaphylactic reactions leading to death.
Hemolytic Disease Of The Newborn: This can occur in pregnant women carrying fetus with a different blood group and can lead to destruction of fetal hemoglobin due to antibodies produced by the mother. Knowing the right type of blood group in such cases is one of the important uses of blood group typing.
Paternity Testing: Only certain blood group combinations from parental blood groups are passed on to the offspring from the parents. Hence, the blood group typing can be used to help in paternity testing as well.