Blood Types

There are twenty-four different blood types known. The most common blood types known are A, B, AB, and O. The knowledge of blood types has saved so many people’s lives. Blood types are also called blood groups. Blood types are inherited, and they never change. Everybody has a blood type. All human blood looks alike, but once tested it shows the differences between the blood.
The letters A, B, AB, and O stand for two antigens labeled A and B. Antigens are substances targeted by the immune system. Group A only has A antigens, group B only has B antigens, group AB has both, and group O has neither. Different races have different percents of blood types, for example, whites may have more O's than blacks do. Below there is a chart of the blood type percents for the different races: White African American Hispanic Asian
O + 37% 47% 53% 39%
O - 8% 4% 4% 1%
A + 33% 24% 29% 27%
A - 7% 2% 2% 0.5%
B + 9% 18% 9% 25%
B - 2% 1% 1% 0.4%
AB + 3% 4% 2% 7%
AB – 1% 0.3% 0.2% 0.1%

Blood types are further classified as Rh-positive and Rh-negative. Blood Rh-positive are found when there is antigen D, and Rh-negative when antigen D isn’t present. Blood type O+ is the most common blood type, but as the chart above shows, not all racial and ethnic groups have the same percent.

Parent 1 AB AB AB AB B A A O O O
Parent 2 AB B A O B B A B A O
Possible
blood type of child O X X X X X X A X X X X X X X B X X X X X X X AB X X X X
Blood types are inherited, like your eye color or your hair type. Your blood type depends on your parents. This next chart shows how you can obtain your blood types from your parents.

These are the possible mixtures that you can obtain from your parents. Any other mixtures would depend on the grandparents, which barely matter in inheriting blood types.
You can’t donate red blood cells to just any person, your blood types have to be compatible. Certain blood