What is Blood Group?
Based on the presence or absence of various antigens, blood is categorized into different groups known as blood groups.
![]() |
Fig: Blood group list |
Before
transfusion of blood to a person, it is necessary to determine the
blood type of the recipients’ blood and the blood type of the donor so
that the blood can be appropriately matched. This is known as blood
groups.
ABO Blood Groups:
It includes-
It includes-
A, B and Rh are the most clinically significant blood antigens present in the RBC membrane.
Importance of Blood Group:
All the key importance of knowing blood group are-
Different Types of Blood Group:
Classical or principal blood groups are listed in the following: ABO Blood Groups:
It includes-
- A,
- B,
- AB,
- O.
It includes-
- Rh +ve,
- Rh –ve.
Basis of Blood Groups:
Blood
groups are determined by the presence or absence of genetically
determined antigens or agglutinogens on the surface of RBCs. A, B and Rh are the most clinically significant blood antigens present in the RBC membrane.
- Type A blood has A antigen on the surface of RBCs.
- Type B blood has B antigen.
- Type AB blood has both A and b antigens.
- Type o blood has neither A nor B antigen.
- Blood with Rh antigen is Rh (+) positive.
- Blood without Rh antigen is RH (-) negative.
ABO System of Blood Grouping: Antigens, Antibodies, and Compatibility:
Blood Group
|
Antigen+ antibody (ies)
present
|
As donor, is
|
As recipient, is
|
A
|
Antigen A makes
Antigen B
|
Compatible with: A and
AB
Incompatible with: B
and O, because both make antigen-A antibodies that will react with A
antigens.
|
Compatible with: A and
O
Incompatible with: B
and AB, because type A makes antigen-B antibodies that will react with B
antigens.
|
B
|
Antigen B makes
Antigen A
|
Compatible with: B
and AB
Incompatible with: A
and O, because both make antigen B antibodies that will react with B
antigens.
|
Compatible with: B
and O
Incompatible with: A
and AB, because types b makes antigen- A antibodies that will react with A
antigens.
|
AB
|
Antigen A and B makes
neither Antigen A nor Antigen B
|
Compatible with: AB
only
Incompatible with: A ,
B and O, because all three make antibodies that will react with AB antigens.
|
Compatible with all
groups “Universal Recipient”
AB makes no antibodies
and therefore will not react with any type of donated blood.
|
O
|
Neither A nor B
antigen makes both Antigen A and Antigen B
|
Compatible with all
groups “Universal Donor”,
O red cells have no
antigens and will therefore not stimulate antigen A or antigen B antibodies.
|
Compatible with: O
only
Incompatible with: A,
AB and b, because type O makes antigen A and antigen B antibodies.
|
Importance of Blood Group:
All the key importance of knowing blood group are-
- To know the blood group of individuals,
- Blood transfusion and tissue transplants,
- Certain blood disease,
- Paternity test and other medico-legal cases.