Question

Person with blood group AB is considered as universal recipient because he has

• A. both A and B antigens on RBC but no antibodies in the plasma
• B. both A and B antibodies in the plasma
• C. no antigen on RBC and no antibody in the plasma
• D. both A and B antigens in the plasma but no antibodies

Answer 1

The correct option is A both A and B antigens on RBC but no antibodies in the plasma

ABO blood groups are determined by the gene I (isoagglutinin). There are alleles, IA, IB and IO of this gene. IA allele is responsible for the formation of A antigen, while IB allele is responsible for the formation of B antigen. People with blood group A have the A antigen on the surface of their RBCs, and antibodies to antigen B in their plasma. Persons with blood group B have B antigen on the surface antigen on their RBCs and antibodies against an antigen in their plasma. Type O individuals are without A and B antigens on their RBCs but have antibodies for both these antigens in their plasma. Individuals with blood group AB can receive blood of A, B or O group, while those with blood group O can donate blood to anyone.