Why is AB a rare blood type?

Blood group AB is one of the rare blood groups, which is characterized by both A and B antigens on red blood cells and no antibodies in the plasma.

In a normal human body, red blood cells are produced in the bone marrow and are responsible for transporting oxygen in the body, each about 2-3 drops of blood contains about 1 billion blood cells. In which, the number of red blood cells far exceeds that of platelets and white blood cells (for every 600 red blood cells, there are about 40 platelets and a single white blood cell).
According to a spokesman for the American Society of Hematology, on the surface of red blood cells there are always proteins attached to carbohydrates, this is also the basic sign that helps to determine which group of blood cells a person belongs to. Normally, there are 8 basic blood types: A, B, AB and O and each type is divided into Rh+ and Rh-.
Blood group A is a group that has only A antigens on the surface of red blood cells, group B has only B antigens, while blood group AB has both antigens and blood group O has no type antigens on the surface of red blood cells. These are the 4 basic and important blood groups to determine whether the patient's blood group can safely receive blood transfusion.
In case the patient receives incompatible blood, it will bring a very dangerous reaction because the immune system will recognize foreign antigens on the surface of blood cells and lead to conflict.

In fact, people with blood type AB are rare and special because they have both A and B antigens on the surface of red blood cells, but no antibodies in the plasma.
All blood types contain basic components such as white blood cells, red blood cells, platelets and plasma (a liquid component in the blood that keeps red and white blood cells and platelets in the system) blood). Red blood cells will be produced in the bone marrow and carry out the job of transporting oxygen to the body, compared to platelets, there are more red blood cells and stop bleeding by clotting and preventing white blood cells. requirements, protect the body from the attack of pathogens and diseases.
Stanford School of Medicine (USA) conducted a survey and calculated the blood type ratio of the general population and gave the following results:
O+: accounted for 37.4% O-: accounted for 6.6% A+: accounted for 35.7% A-: accounted for 6.3% B+: accounted for 8.5% B-: accounted for 1.5% AB+: accounted for 3.4% AB-: accounted for 0.6% However, this is only the percentage in general and in practice there are slight differences on the basis of ethnicity. People with blood type B are more common in Asia than white people, while blood type O is more common in Spain.

People with blood type AB can be inherited, gene A from father and gene B from mother. Owners of this rare blood type have a great advantage of being able to receive any blood type, especially blood type AB +. However, because of the presence of both antigens on type AB red blood cells, people with this type of blood can only donate blood to people with the same AB blood type. In the case of blood group AB with Rh-, it is only possible to receive blood from people with Rh- blood group because if received from people with Rh+, it can cause dangerous complications when transfusion.
In fact, people with rare blood types who need an urgent blood transfusion due to an accident of blood loss or undergoing an emergency surgery... do not always have a backup blood source available in the hospital. room. Therefore, if you are a blood type AB owner, you should actively take care of yourself and send blood to a blood bank in case you need it, if possible, join the association of people with rare blood type. to help each other when needed.