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Introduction
People come in all different shapes, sizes and blood types. The vast majority of blood types fall into one of the major ABO groups. However, for a small percentage of the population,finding someone else with the same blood type can be as difficult as looking for a needle in a haystack.
Certain blood types are unique to specific racial and ethnic groups. Therefore it isessential that the donor diversity match the patient diversity.
Blood types
If we are going to talk about blood diversity, we have to also talk about blood types.
Although all blood is made of the samebasic elements, not all blood is alike. In fact, there are eight different common blood types, which are determined by the presence or absence of certain antigens – substances that can trigger animmune response if they are foreign to the body. Since some antigens can trigger a patient's immune system to attack the transfused blood, safe blood transfusions depend on careful blood typing andcross-matching.
The ABO Blood Group System
There are four major blood groups determined by the presence or absence of two antigens – A and B – on the surface of red blood cells:

Group A – has onlythe A antigen on red cells (and B antibody in the plasma) |
Group B – has only the B antigen on red cells (and A antibody in the plasma) |
Group AB – has both A and B antigens on red cells (butneither A nor B antibody in the plasma) |
Group O – has neither A nor B antigens on red cells (but both A and B antibody are in the plasma) |

Some rare blood types
Ethnic Group | Rare BloodType |
African-American | U-, Fy(a-b-) |
Native American, Alaskan Native | RzRz |
Pacific Island, Asian | Jk (a-b-) |
Hispanic | Di(b-) |
East European/Russian Jews | Dr(a-) |Caucasian | Kp(b-), Vel- |

Importance of type O
Different ethnic and racial groups also have different frequency of the main blood types in their populations. For example, approximately 45 percent of...