In 1901 it was established that we humans have different blood groups. We know today that there are four main blood groups that are divided into another eight blood groups using the rhesus system.
Blood group The distribution among the world’s population is, however, far from even and since the beginning, doctors have asked themselves what our blood groups can tell us – and what they mean.
How is a blood type determined?
When a blood group is to be determined, the two most important blood group systems are used: the AB0 and the RhD system.
The AB0 system
The AB0 system is what determines your parent blood group and can therefore be considered the most important blood group system. The blood type here is determined by the antigens A and B, which are found on the surface of the red blood cells. Which antigens the red blood cells are covered by differs from person to person and some have none at all. In this way, the blood group is determined by the presence or absence of the current antigen after which the blood group is named (A, B, AB and 0).
The RhD system
The other important blood group system is the rhesus system, which consists of the types of rhesus negative and rhesus positive. Here, the four main blood groups are divided according to whether they contain the antigen D, whereupon a person is RhD-positive or if they do not, whereupon one is RhD-negative.
When these two blood group systems are connected, it gives eight blood types:
- A RhD neg
- A Rhd pos
- 0 RhD neg
- 0 RhD pos
- B RhD neg
- B RhD pos
- AB RhD neg
- AB RhD pos
You can read more about RhD negatives and other blood groups here.
Rhesus negative requires extra attention
It is especially important to know their rhesus status as a mixture of the two blood groups can cause serious complications for RhD-negatives. This is one of the reasons why it is always one of the first things that is decided by patients and donors.
Rhesus negative and blood transfusion
When donating blood, donors and recipients often have the same type of rhesus (ie RhD-positive blood for RhD-positive recipients and RhD-negative blood for RhD-negative recipients). As a rhesus positive, you have the RhD antigen, which is a protein on the red blood cells. If you are rhesus negative, you do not have the RhD antigen (you are missing this protein).
The above means that rhesus-negative donor blood can also be used for recipients who are rhesus-positive. However, this is not the opposite. If a rhesus-negative person receives a transfusion with rhesus-positive blood, it can lead to very serious transfusion complications. Anti-D is, among other things, one of the main causes of the serious disease congenital jaundice in newborns. Under normal circumstances, therefore, RhD-negative blood will only be given to RhD-negative patients.
Is there universal blood?
Yes, there is universal blood and it is a vital cure. If one day you need an acute blood transfusion – for example after a traffic accident – and your blood type is unknown, the transfusion is performed with universal blood.
Blood type 0 rhesus D neg is called universal blood because it can be transfused without the risk of antibody formation against A and B, while eliminating the risk of antibody formation in rhesus D neg.
In the case of transfusion with universal blood, the blood bank simultaneously determines the patient’s blood group acutely, which takes less than half an hour. The patient is then allowed to undergo a transfusion of his or her own blood type.
If we have aroused your interest in the body and differences in blood groups, you can find more articles from Illustrated Science here.
Source: Plato Data Intelligence: PlatoData.io
