Why take a blood type test?
Did you know that blood types are most likely linked to your individual risk of developing certain diseases? For example, scientists suspect that people with blood type 0 have a lower risk of cardiovascular disease and dementia but are more susceptible to certain infectious diseases, such as tuberculosis and cholera.
In medicine, blood types are particularly important for blood transfusions. When a person receives a blood donation, the blood types must match, so that the body does not reject the new blood.
Blood group tests are also used to prove a blood type match. As certain blood types are particularly common in certain regions and population groups, they can be used to find out the origin of ancestors.
Important: if DNA analysis reveals a blood type that may be linked to a greater risk of certain diseases, it does not mean that you will also develop that disease! These genetic predispositions are only an indication of the likelihood and possibility of developing certain health problems.
How does the DNA Blood Type Test work?
For the blood group test, you need to collect a small saliva sample from the mucous membrane of your mouth. To do this, a cotton swab is included in the test kit, with which you can place your samples into a sample tube. You then send the saliva samples to us to be analysed in a specialised medical laboratory.
Our specialised laboratory performs complex DNA sequencing. The duration of the analysis depends on the quality of the sample provided – sometimes, the laboratory has to repeat the analysis several times. It may therefore take a few weeks before you receive the test results.
How can I provide a high-quality saliva sample?
The higher the quality of the sample, the quicker and easier the laboratory can analyse it. You can help by following these guidelines when taking the sample:
- You should not eat or drink anything for at least half an hour before the sample is taken.
- Do not brush your teeth or use mouthwash during this time.
- Do not smoke for half an hour before the test.
- The sample should be kept dry for 24 hours before being sent. During this time, the sample can dry in the sample tube.
What does the results report tell me?
Based on the genes analysed, the DNA test results report gives you information about your blood type according to 15 different blood group systems.
The following blood group systems are analysed:
- AB0
- Rh factor
- Kell
- Duffy
- Lutheran
- Kidd
- Diego/Wright
- Cartwright
- Scianna
- Dombrock
- Colton
- Landsteiner
- Vel
- MNS
- Indian
Why are there different blood types?
The blood of humans differs in many aspects – these aspects are described in terms of blood group systems. In most cases, it is a question of whether or not certain antigens, special proteins, are present in the blood. Blood groups are determined genetically. In general, your blood type stays the same for your entire life.
Your immune system forms antibodies depending on the antigens present in your body. These antibodies in turn act against other antigens – this is why the blood of some blood types does not match.
When it comes to blood donation, doctors test the blood of the recipient and the donor for at least the AB0 system and the Rhesus factor to prevent complications during transfusions.
What is the AB0 blood group system?
The best-known blood group system divides blood into blood groups A, B, AB and 0. Blood groups depend on whether or not the two antigens A and B are present in the blood:
- Blood group A has only the A antigen
- Blood group B has only the B antigen
- Blood group AB has both antigens
- Blood group 0 has neither antigen
Depending on our blood type, our bodies form certain antibodies. For example, people with blood type A develop anti-B antibodies, which means that blood containing B antigens is rejected by their bodies.
People with blood type AB do not form antibodies at all; they are considered universal recipients and can receive blood from all other blood types. People with blood type 0 are universal donors – these people can give blood to anyone, but can only receive blood from other people with blood type 0.
What is the Rhesus factor?
Besides the AB0 system, the Rhesus system is the most important characteristic for blood transfusions. This blood group system tells us whether people have the rhesus factor D or not. If they have this protein in their blood, they are Rhesus positive – as are the majority of people in Europe. Only about 15 per cent of the population are Rhesus negative, meaning they do not have Rhesus factor D.
The Rhesus factor is also crucial for blood donations. If you are Rhesus negative, you can only receive blood from other Rhesus-negative people. Rhesus-positive people can receive both Rhesus-negative and Rhesus-positive blood.
Different Rhesus antibodies can also lead to incompatible blood groups between a mother and foetus during pregnancy. A possible consequence of this is that the infant develops anaemia.
In medicine, the two systems are combined by adding a ‘+’ or ‘–’ to the AB0 group. For people who have A antigens but no B antigens and who also have the Rhesus factor D, the blood group A+.
What is the Kell blood group system?
The third most important blood group system for blood donations, after AB0 and the Rh factor, is the Kell system. This system consists of three antigens that can be present in your blood.
The Kell blood group can also lead to complications during pregnancy if a mother has different Kell antigens to the child – as is the case when they have different Rhesus factors.
How is blood type linked to disease?
Malaria is one example. This infectious disease is particularly common in parts of Africa. At the same time, blood group 0 is particularly prevalent on the continent, as is the Duffy-negative blood group, which is particularly common in malaria-endemic areas. Both types – blood group 0 and Duffy-negative – could contribute to protection against the malaria pathogen and have therefore prevailed in these areas.
This shows that there are indeed links between your blood type and protection against diseases – and that it may be worth paying special attention to preventing certain diseases based on your blood type.
How is blood type linked to Covid-19?
Researchers have been able to identify differences in the severity of Covid-19 in people – these differences are related to blood type.
In the studies, people with blood type 0 had less severe infections than those affected by other blood types in the AB0 system. So, it is possible that blood type 0 brings with it some element of protection against the virus – but that doesn’t mean you can’t get seriously ill if you have blood type 0; this risk is probably only slightly reduced.
Who should NOT take the test?
The DNA Blood Type Test is not or only partially suitable for certain groups of people:
- People with infectious diseases, like hepatitis and HIV, may not use the DNA Blood Type Test.
- Pregnant and breastfeeding women should only take the hsCRP Test under medical supervision. The given reference ranges and recommendations do not apply to people in this group; consult your medical professional for advice concerning your test results.
- The DNA Blood Type Test is not intended for children under 18 years of age..
- The test is not intended for diagnosing illnesses or diseases. For example, if you suffer from moderate pain, consult a doctor.