Which of the following blood grouping systems is characterized by the presence of a high-frequency antigen that is expressed on the red blood cells of most individuals, but is absent in a small percentage of the population?
Explanation
The Vel blood group system is characterized by the presence of a high-frequency antigen that is expressed on the red blood cells of most individuals, but is absent in a small percentage of the population.
Source
Transfusion Medicine by Rossi











