Blood Grouping
Blood types
Karl Landsteiner discovered blood groups, 1901.
Membrane of red blood cell contain blood group antigens - agglutinogens
Several types of antigens.
Most important – ABO system and Rh.
Less important - MNSs, Lutheran, Kell, Kidd
ABO system
4 major blood groups.
A – antigen A
B – antigen B
AB – antigen A & B
O – no antigen
Found in other tissue – Kidney, liver, lungs.
All type contain H antigen on cell surface.
A type – acetylgalactosamin
B type – galactose
AB – Both
O – only H antigen
Antibody against RBC antigen – agglutinins.
Antibody develop after birth due GIT bacteria/food
No antibody development against antigen present in own cells.
Inheritance of ABO system
Inherited as mendelian allelomorphs.
Phenotype B – Genotype BB (homozygous) or BO (heterozygous).
When blood type of parents know possible genotypes can be predicted.
If mother’s and child’s blood type know, it can be prove that a man can’t be father.
Rh blood group
Rh factor named for rhesus monkey.
Only found in RBC.
C,D,E (and more) antigen – Most important is D.
Rh positive mean antigen D present.
85% Caucasians, 99% Asians are Rh positive.
Rh blood group
Rh negative person can produce anti-D antibody when expose to antigen D.
Anti-D antibody will not develop without expose antigen D.
To develop anti-D need transfusion
from other person
from fetal blood to mother.