Part of
Blood Type
Blood Group
Blood group identifies the specific antigens on red blood cells, determining compatibility for blood transfusions and organ transplants.
Blood Group
Normal range
Normal range
A, B, AB, O
A, B, AB, O
Normal range
A, B, AB, O
A, B, AB, O
Normal range
Blood Group
Blood Group
Blood group identifies the specific antigens on red blood cells, determining compatibility for blood transfusions and organ transplants.
Blood Group
Normal range
A, B, AB, O
Normal range
A, B, AB, O
A, B, AB, O
Normal range
Blood Group
Blood Group
Blood group identifies the specific antigens on red blood cells, determining compatibility for blood transfusions and organ transplants.
Blood Group
Normal range
A, B, AB, O
Normal range
A, B, AB, O
A, B, AB, O
Normal range
Blood Group
Blood Group
Blood group identifies the specific antigens on red blood cells, determining compatibility for blood transfusions and organ transplants.
Blood Group
Normal range
A, B, AB, O
Normal range
A, B, AB, O
A, B, AB, O
Normal range
Blood Group
Dr. Yiannis Balanos
MBBS MRCGP
Your Genetic Blood Type Identity
Your Genetic Blood Type Identity
Your Genetic Blood Type Identity
Your ABO blood group is a fundamental characteristic determined entirely by the genes you inherited from your parents. The ABO system classifies blood into four main types—A, B, AB, and O—based on specific markers called antigens present on the surface of your red blood cells. This blood group remains constant throughout your life and plays a critical role in safe blood transfusions, organ transplants, and pregnancy management.
Understanding your blood group is important for medical safety. Your immune system naturally produces antibodies against blood group antigens you don't have, which means receiving incompatible blood can trigger a serious, potentially life-threatening immune reaction. This is why blood group testing is essential before any transfusion or transplant procedure.
Your ABO blood group is a fundamental characteristic determined entirely by the genes you inherited from your parents. The ABO system classifies blood into four main types—A, B, AB, and O—based on specific markers called antigens present on the surface of your red blood cells. This blood group remains constant throughout your life and plays a critical role in safe blood transfusions, organ transplants, and pregnancy management.
Understanding your blood group is important for medical safety. Your immune system naturally produces antibodies against blood group antigens you don't have, which means receiving incompatible blood can trigger a serious, potentially life-threatening immune reaction. This is why blood group testing is essential before any transfusion or transplant procedure.
Understanding the Four ABO Blood Groups
Understanding the Four ABO Blood Groups
Understanding the Four ABO Blood Groups
Understanding the Four ABO Blood Groups
Discover what makes each blood group unique and how the presence or absence of A and B antigens determines your blood type.
Read more
How ABO Blood Groups Are Inherited
How ABO Blood Groups Are Inherited
How ABO Blood Groups Are Inherited
How ABO Blood Groups Are Inherited
Learn about the genetic patterns that determine your blood group and why your type depends on the combination of genes from both parents.
Read more
Why Your Blood Group Matters
Why Your Blood Group Matters
Why Your Blood Group Matters
Why Your Blood Group Matters
Explore the medical importance of blood groups in transfusions, transplants, pregnancy, and why compatibility is crucial for safety.
Read more
Understanding Your Blood Group Test
Understanding Your Blood Group Test
Understanding Your Blood Group Test
Understanding Your Blood Group Test
Find out how blood group testing works, when it's performed, and what your results mean for your healthcare.
Read more
Understanding the Four ABO Blood Groups:
The ABO blood group system categorises blood into four main types based on which antigens are present on your red blood cells. The A and B alleles are codominant, and the O allele is recessive.
Blood Group A means you have A antigens on your red blood cells and naturally produce anti-B antibodies in your plasma. These antibodies would attack any B antigens if you received group B blood, making compatibility crucial for safe transfusions.
Blood Group B means you have B antigens on your red blood cells and naturally produce anti-A antibodies in your plasma. Your immune system would react against group A blood, recognising it as foreign.
Blood Group AB means you have both A and B antigens on your red blood cells. Importantly, you don't produce anti-A or anti-B antibodies, which makes AB individuals "universal recipients" who can receive blood from any ABO group in emergency situations.
Blood Group O means you have neither A nor B antigens on your red blood cells, but you produce both anti-A and anti-B antibodies. This makes group O individuals "universal donors" whose red blood cells can be given to patients of any ABO blood group in emergencies.
In the UK, the distribution of blood groups varies, with approximately 47% of people having group O, 42% having group A, 9% having group B, and about 3% having group AB.
Understanding the Four ABO Blood Groups:
The ABO blood group system categorises blood into four main types based on which antigens are present on your red blood cells. The A and B alleles are codominant, and the O allele is recessive.
Blood Group A means you have A antigens on your red blood cells and naturally produce anti-B antibodies in your plasma. These antibodies would attack any B antigens if you received group B blood, making compatibility crucial for safe transfusions.
Blood Group B means you have B antigens on your red blood cells and naturally produce anti-A antibodies in your plasma. Your immune system would react against group A blood, recognising it as foreign.
Blood Group AB means you have both A and B antigens on your red blood cells. Importantly, you don't produce anti-A or anti-B antibodies, which makes AB individuals "universal recipients" who can receive blood from any ABO group in emergency situations.
Blood Group O means you have neither A nor B antigens on your red blood cells, but you produce both anti-A and anti-B antibodies. This makes group O individuals "universal donors" whose red blood cells can be given to patients of any ABO blood group in emergencies.
In the UK, the distribution of blood groups varies, with approximately 47% of people having group O, 42% having group A, 9% having group B, and about 3% having group AB.
Understanding the Four ABO Blood Groups:
The ABO blood group system categorises blood into four main types based on which antigens are present on your red blood cells. The A and B alleles are codominant, and the O allele is recessive.
Blood Group A means you have A antigens on your red blood cells and naturally produce anti-B antibodies in your plasma. These antibodies would attack any B antigens if you received group B blood, making compatibility crucial for safe transfusions.
Blood Group B means you have B antigens on your red blood cells and naturally produce anti-A antibodies in your plasma. Your immune system would react against group A blood, recognising it as foreign.
Blood Group AB means you have both A and B antigens on your red blood cells. Importantly, you don't produce anti-A or anti-B antibodies, which makes AB individuals "universal recipients" who can receive blood from any ABO group in emergency situations.
Blood Group O means you have neither A nor B antigens on your red blood cells, but you produce both anti-A and anti-B antibodies. This makes group O individuals "universal donors" whose red blood cells can be given to patients of any ABO blood group in emergencies.
In the UK, the distribution of blood groups varies, with approximately 47% of people having group O, 42% having group A, 9% having group B, and about 3% having group AB.
Understanding the Four ABO Blood Groups:
The ABO blood group system categorises blood into four main types based on which antigens are present on your red blood cells. The A and B alleles are codominant, and the O allele is recessive.
Blood Group A means you have A antigens on your red blood cells and naturally produce anti-B antibodies in your plasma. These antibodies would attack any B antigens if you received group B blood, making compatibility crucial for safe transfusions.
Blood Group B means you have B antigens on your red blood cells and naturally produce anti-A antibodies in your plasma. Your immune system would react against group A blood, recognising it as foreign.
Blood Group AB means you have both A and B antigens on your red blood cells. Importantly, you don't produce anti-A or anti-B antibodies, which makes AB individuals "universal recipients" who can receive blood from any ABO group in emergency situations.
Blood Group O means you have neither A nor B antigens on your red blood cells, but you produce both anti-A and anti-B antibodies. This makes group O individuals "universal donors" whose red blood cells can be given to patients of any ABO blood group in emergencies.
In the UK, the distribution of blood groups varies, with approximately 47% of people having group O, 42% having group A, 9% having group B, and about 3% having group AB.
How ABO Blood Groups Are Inherited
Blood groups are inherited from both parents. The ABO blood type is controlled by a single gene (the ABO gene) with three types of alleles: A, B, and O. You inherit one allele from each parent, and the combination determines your blood group.
The inheritance follows predictable patterns. If you inherit an A allele from one parent and an O allele from the other, you'll have blood group A (the A allele is dominant over O). Similarly, inheriting B and O results in blood group B. If you inherit both A and B alleles, you'll have blood group AB, as both are codominant. Blood group O only occurs when you inherit O alleles from both parents.
Your ABO blood group is set at conception and remains unchanged throughout your life. Unlike many other biological markers that can fluctuate with health, diet, or age, your blood group is a permanent genetic characteristic.
How ABO Blood Groups Are Inherited
Blood groups are inherited from both parents. The ABO blood type is controlled by a single gene (the ABO gene) with three types of alleles: A, B, and O. You inherit one allele from each parent, and the combination determines your blood group.
The inheritance follows predictable patterns. If you inherit an A allele from one parent and an O allele from the other, you'll have blood group A (the A allele is dominant over O). Similarly, inheriting B and O results in blood group B. If you inherit both A and B alleles, you'll have blood group AB, as both are codominant. Blood group O only occurs when you inherit O alleles from both parents.
Your ABO blood group is set at conception and remains unchanged throughout your life. Unlike many other biological markers that can fluctuate with health, diet, or age, your blood group is a permanent genetic characteristic.
How ABO Blood Groups Are Inherited
Blood groups are inherited from both parents. The ABO blood type is controlled by a single gene (the ABO gene) with three types of alleles: A, B, and O. You inherit one allele from each parent, and the combination determines your blood group.
The inheritance follows predictable patterns. If you inherit an A allele from one parent and an O allele from the other, you'll have blood group A (the A allele is dominant over O). Similarly, inheriting B and O results in blood group B. If you inherit both A and B alleles, you'll have blood group AB, as both are codominant. Blood group O only occurs when you inherit O alleles from both parents.
Your ABO blood group is set at conception and remains unchanged throughout your life. Unlike many other biological markers that can fluctuate with health, diet, or age, your blood group is a permanent genetic characteristic.
How ABO Blood Groups Are Inherited
Blood groups are inherited from both parents. The ABO blood type is controlled by a single gene (the ABO gene) with three types of alleles: A, B, and O. You inherit one allele from each parent, and the combination determines your blood group.
The inheritance follows predictable patterns. If you inherit an A allele from one parent and an O allele from the other, you'll have blood group A (the A allele is dominant over O). Similarly, inheriting B and O results in blood group B. If you inherit both A and B alleles, you'll have blood group AB, as both are codominant. Blood group O only occurs when you inherit O alleles from both parents.
Your ABO blood group is set at conception and remains unchanged throughout your life. Unlike many other biological markers that can fluctuate with health, diet, or age, your blood group is a permanent genetic characteristic.
Why Your Blood Group Matters
The ABO blood group system is critically important for medical safety, particularly in transfusions and transplants. The antibodies bind to transfused red cells carrying the corresponding antigen and trigger an immune response, causing the red cells to haemolyse. This reaction, known as acute haemolytic transfusion reaction, can be life-threatening.
If a patient is likely to require a blood transfusion they must first have their ABO and Rh D type determined, as well as being screened for the presence of antibodies to other blood group antigens. This testing ensures that compatible blood is available when needed, preventing dangerous transfusion reactions.
Blood group compatibility follows specific rules:
Group O can donate to all groups (universal donor for red cells)
Group AB can receive from all groups (universal recipient)
Group A can donate to A and AB, and receive from A and O
Group B can donate to B and AB, and receive from B and O
In organ transplantation, ABO compatibility is also essential. Transplanting an organ from an incompatible donor can lead to organ rejection.
During pregnancy, knowing your blood group helps healthcare providers monitor for potential issues, particularly when combined with Rh factor information.
Why Your Blood Group Matters
The ABO blood group system is critically important for medical safety, particularly in transfusions and transplants. The antibodies bind to transfused red cells carrying the corresponding antigen and trigger an immune response, causing the red cells to haemolyse. This reaction, known as acute haemolytic transfusion reaction, can be life-threatening.
If a patient is likely to require a blood transfusion they must first have their ABO and Rh D type determined, as well as being screened for the presence of antibodies to other blood group antigens. This testing ensures that compatible blood is available when needed, preventing dangerous transfusion reactions.
Blood group compatibility follows specific rules:
Group O can donate to all groups (universal donor for red cells)
Group AB can receive from all groups (universal recipient)
Group A can donate to A and AB, and receive from A and O
Group B can donate to B and AB, and receive from B and O
In organ transplantation, ABO compatibility is also essential. Transplanting an organ from an incompatible donor can lead to organ rejection.
During pregnancy, knowing your blood group helps healthcare providers monitor for potential issues, particularly when combined with Rh factor information.
Why Your Blood Group Matters
The ABO blood group system is critically important for medical safety, particularly in transfusions and transplants. The antibodies bind to transfused red cells carrying the corresponding antigen and trigger an immune response, causing the red cells to haemolyse. This reaction, known as acute haemolytic transfusion reaction, can be life-threatening.
If a patient is likely to require a blood transfusion they must first have their ABO and Rh D type determined, as well as being screened for the presence of antibodies to other blood group antigens. This testing ensures that compatible blood is available when needed, preventing dangerous transfusion reactions.
Blood group compatibility follows specific rules:
Group O can donate to all groups (universal donor for red cells)
Group AB can receive from all groups (universal recipient)
Group A can donate to A and AB, and receive from A and O
Group B can donate to B and AB, and receive from B and O
In organ transplantation, ABO compatibility is also essential. Transplanting an organ from an incompatible donor can lead to organ rejection.
During pregnancy, knowing your blood group helps healthcare providers monitor for potential issues, particularly when combined with Rh factor information.
Why Your Blood Group Matters
The ABO blood group system is critically important for medical safety, particularly in transfusions and transplants. The antibodies bind to transfused red cells carrying the corresponding antigen and trigger an immune response, causing the red cells to haemolyse. This reaction, known as acute haemolytic transfusion reaction, can be life-threatening.
If a patient is likely to require a blood transfusion they must first have their ABO and Rh D type determined, as well as being screened for the presence of antibodies to other blood group antigens. This testing ensures that compatible blood is available when needed, preventing dangerous transfusion reactions.
Blood group compatibility follows specific rules:
Group O can donate to all groups (universal donor for red cells)
Group AB can receive from all groups (universal recipient)
Group A can donate to A and AB, and receive from A and O
Group B can donate to B and AB, and receive from B and O
In organ transplantation, ABO compatibility is also essential. Transplanting an organ from an incompatible donor can lead to organ rejection.
During pregnancy, knowing your blood group helps healthcare providers monitor for potential issues, particularly when combined with Rh factor information.
Understanding Your Blood Group Test
Blood group testing is straightforward and involves taking a small blood sample, typically from a vein in your arm. The laboratory tests your blood against different antibodies to determine which antigens are present on your red blood cells.
Testing is routinely performed:
Before any planned surgery where transfusion might be needed
During pregnancy as part of antenatal screening
When registering as a blood donor
Before organ or tissue transplantation
After birth for newborns in some circumstances
Your blood group test result will indicate your ABO type (A, B, AB, or O). This information is usually recorded in your medical records and remains valid for life, though hospitals typically verify your blood group with a fresh sample before any transfusion or procedure.
If you're a blood donor, you'll receive a donor card showing your blood group. Many people first learn their blood group when they donate blood or during pregnancy. Some people may also discover their blood group through DNA testing services, though medical-grade testing is required for clinical purposes.
Your blood group result doesn't change with age, illness, or lifestyle factors. Once established, this genetic characteristic provides permanent information that remains relevant throughout your healthcare journey.
Understanding Your Blood Group Test
Blood group testing is straightforward and involves taking a small blood sample, typically from a vein in your arm. The laboratory tests your blood against different antibodies to determine which antigens are present on your red blood cells.
Testing is routinely performed:
Before any planned surgery where transfusion might be needed
During pregnancy as part of antenatal screening
When registering as a blood donor
Before organ or tissue transplantation
After birth for newborns in some circumstances
Your blood group test result will indicate your ABO type (A, B, AB, or O). This information is usually recorded in your medical records and remains valid for life, though hospitals typically verify your blood group with a fresh sample before any transfusion or procedure.
If you're a blood donor, you'll receive a donor card showing your blood group. Many people first learn their blood group when they donate blood or during pregnancy. Some people may also discover their blood group through DNA testing services, though medical-grade testing is required for clinical purposes.
Your blood group result doesn't change with age, illness, or lifestyle factors. Once established, this genetic characteristic provides permanent information that remains relevant throughout your healthcare journey.
Understanding Your Blood Group Test
Blood group testing is straightforward and involves taking a small blood sample, typically from a vein in your arm. The laboratory tests your blood against different antibodies to determine which antigens are present on your red blood cells.
Testing is routinely performed:
Before any planned surgery where transfusion might be needed
During pregnancy as part of antenatal screening
When registering as a blood donor
Before organ or tissue transplantation
After birth for newborns in some circumstances
Your blood group test result will indicate your ABO type (A, B, AB, or O). This information is usually recorded in your medical records and remains valid for life, though hospitals typically verify your blood group with a fresh sample before any transfusion or procedure.
If you're a blood donor, you'll receive a donor card showing your blood group. Many people first learn their blood group when they donate blood or during pregnancy. Some people may also discover their blood group through DNA testing services, though medical-grade testing is required for clinical purposes.
Your blood group result doesn't change with age, illness, or lifestyle factors. Once established, this genetic characteristic provides permanent information that remains relevant throughout your healthcare journey.
Understanding Your Blood Group Test
Blood group testing is straightforward and involves taking a small blood sample, typically from a vein in your arm. The laboratory tests your blood against different antibodies to determine which antigens are present on your red blood cells.
Testing is routinely performed:
Before any planned surgery where transfusion might be needed
During pregnancy as part of antenatal screening
When registering as a blood donor
Before organ or tissue transplantation
After birth for newborns in some circumstances
Your blood group test result will indicate your ABO type (A, B, AB, or O). This information is usually recorded in your medical records and remains valid for life, though hospitals typically verify your blood group with a fresh sample before any transfusion or procedure.
If you're a blood donor, you'll receive a donor card showing your blood group. Many people first learn their blood group when they donate blood or during pregnancy. Some people may also discover their blood group through DNA testing services, though medical-grade testing is required for clinical purposes.
Your blood group result doesn't change with age, illness, or lifestyle factors. Once established, this genetic characteristic provides permanent information that remains relevant throughout your healthcare journey.
The Takeaway
Your ABO blood group is a fundamental genetic characteristic that plays a vital role in medical safety. Understanding your blood group is important for ensuring compatible transfusions, successful transplants, and appropriate pregnancy care.
The ABO system demonstrates how genetics directly impacts healthcare. This single genetic trait, determined at conception, remains one of the most clinically important pieces of information in modern medicine.
The Takeaway
Your ABO blood group is a fundamental genetic characteristic that plays a vital role in medical safety. Understanding your blood group is important for ensuring compatible transfusions, successful transplants, and appropriate pregnancy care.
The ABO system demonstrates how genetics directly impacts healthcare. This single genetic trait, determined at conception, remains one of the most clinically important pieces of information in modern medicine.
The Takeaway
Your ABO blood group is a fundamental genetic characteristic that plays a vital role in medical safety. Understanding your blood group is important for ensuring compatible transfusions, successful transplants, and appropriate pregnancy care.
The ABO system demonstrates how genetics directly impacts healthcare. This single genetic trait, determined at conception, remains one of the most clinically important pieces of information in modern medicine.
The Takeaway
Your ABO blood group is a fundamental genetic characteristic that plays a vital role in medical safety. Understanding your blood group is important for ensuring compatible transfusions, successful transplants, and appropriate pregnancy care.
The ABO system demonstrates how genetics directly impacts healthcare. This single genetic trait, determined at conception, remains one of the most clinically important pieces of information in modern medicine.
References
NHS. (2024). Blood groups.
NHS Blood and Transplant. (2024). Blood group basics.
Blackpool Teaching Hospitals NHS Foundation Trust. (2024). ABO and RhD group and antibody screen.
Dean L. Blood Groups and Red Cell Antigens. Bethesda (MD): National Center for Biotechnology Information (US); 2005. Chapter 5, The ABO blood group.
References
NHS. (2024). Blood groups.
NHS Blood and Transplant. (2024). Blood group basics.
Blackpool Teaching Hospitals NHS Foundation Trust. (2024). ABO and RhD group and antibody screen.
Dean L. Blood Groups and Red Cell Antigens. Bethesda (MD): National Center for Biotechnology Information (US); 2005. Chapter 5, The ABO blood group.
References
NHS. (2024). Blood groups.
NHS Blood and Transplant. (2024). Blood group basics.
Blackpool Teaching Hospitals NHS Foundation Trust. (2024). ABO and RhD group and antibody screen.
Dean L. Blood Groups and Red Cell Antigens. Bethesda (MD): National Center for Biotechnology Information (US); 2005. Chapter 5, The ABO blood group.
References
NHS. (2024). Blood groups.
NHS Blood and Transplant. (2024). Blood group basics.
Blackpool Teaching Hospitals NHS Foundation Trust. (2024). ABO and RhD group and antibody screen.
Dean L. Blood Groups and Red Cell Antigens. Bethesda (MD): National Center for Biotechnology Information (US); 2005. Chapter 5, The ABO blood group.
Research articles
Research articles
Research articles
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