"Landsteiner" discovered the blood group in 1900 and is called as "Father of blood group".
According to the Landsteiner's law, people are classified into three types of blood group depending on presence and/or absence of antigen. The varieties of glycoprotein coating on red blood cells divides into blood groups.
There are two types of antigens,
- A agglutinogen
- B agglutinogen
Thus people belong to A, B and O blood groups.
If antigen A is present in RBC, the blood group is A. – A oligosaccharide is present
If antigen B is present in RBC, the blood group is B. – B oligosaccharide is present
If no antigen is present in RBC, the blood group is O. – (neither A nor B, only their precursor H oligosaccharide present)
Another blood group is discovered by De Castallo. - If both antigen is present in RBC, the blood group is AB. – A & B oligosaccharides are present
|A||A Antigen||Beta Anitbody|
|B||B Antigen||Alpha Antibody|
|AB||A & B Antigen||-|
|O||-||Alpha & Beta Antibody|
If an agglutinogen is present in RBC of a person, the corresponding agglutinin may be absent.
If an agglutinogen is absent in RBC, the corresponding agglutinin must be present.
Mismatched Blood Transfusion:
During blood transfusion, only compatible blood can be used. The person who gives blood is known as donor and who receives blood is known as recipient.
The antigen of donor and antibody of recipient should be given importance.
1. If an agglutinogen is mixed with corresponding agglutinin, agglutination occurs.
2. Agglutination is clumping of separate RBC.
3. If mismatched blood is transfused to a person, transfusion reaction occurs.
If recipient plasma contains agglutinin against donor's RBC, the donor's RBCs are destroyed and agglutinated. More amount of haemoglobin and toxins released in blood cause complications of jaundice, cardiac shock, renal shut down, etc
Other blood groups are: Levis blood group, MNS blood group