is AB-, with less than 1% of the population having this type. The rarity of and demand for this type of blood emphasize the importance of blood donors.Ĭlick here to learn more about blood types. For this reason, some blood centers collect ethnic information from blood donors.įor some conditions, such as thalassemia and sickle cell disease, this matching is even more important because these conditions are more common among certain ethnic communities, and people may need frequent transfusions.įor example, only 2% of donors have a rare subtype of blood that doctors often use to treat sickle cell disease, but demand for it is increasing by 10–15% each year. To increase the likelihood of well-matched blood types, experts recommend matching donors and recipients along ethnic lines, particularly for rare blood types. Inherited characteristics, such as blood types, tend to run in ethnic groups. Due to this genetic factor, the American Red Cross suggest that when people need blood, especially those with rare blood types, the best matches tend to come from people of the same race or ethnic background. The genes that a person inherits from their parents determine the mix of antigens and proteins in their blood. If it is present, the blood group is Rh-positive, but if it is absent, the blood group is Rh-negative.Ĭombining these two characteristics yields the eight most common blood types. Red blood cells may have another antigen called the Rh antigen on their surface. Blood group AB has both A and B antigens.Blood group O has neither A nor B antigens.

Blood group A has A antigens on the red blood cells.This system classifies blood types as follows: These define blood types according to which antigens are present on red blood cells. People can define blood types using the ABO and Rhesus (Rh) blood group systems. Share on Pinterest A person’s blood type may fall into any of the 36 human blood groups.

Rare a negative blood type