ABO blood group
There are four principal types of blood: A, B, O and AB. There are two antigens and two antibodies that are mostly responsible for the ABO types. The combination of these four components determines an individual’s type in most cases.
The type 0 blood well-known as the Universal donor do not produce antigens AB so this type of blood is not rejected by others with other types of blood. Opposite to this the AB type of blood produces both antigens AB but does not produce antibodies. These are known as universal receivers.
ABO blood types are inherited
Ludwick Hirszfeld and Emil von Dungern discovered that ABO blood types are inherited. The result from receiving 1 of 3 alleles from each parent. The possible outcomes are shown below:
Largest blood type in the world
Blood group O is the most common blood group. For instance, almost half of the UK population (48%) has a blood group O. Red blood cells sometimes have another antigen RhD if this is present your blood type is positive, if it is not, it will be negative. This makes the total of the combination of 8 blood types. A 36% of the UK population is O+. The blood type O- is the one given when the blood type of the recipient is unknown, for instance, in an emergency.