Blood Group Basics
There are eight blood groups and they are classified using two systems.
- ABO System
- Rhesus system
The first system is called the ABO System and it has four main groups:
- O Group
- A Group
- B Group
- AB Group
The second system is called the Rhesus System and is classified as Rhesus Positive (+) and Rhesus Negative (-). The two systems combine to define the following of eight different blood groups of O-, O+, A-, A+, B-, B+, AB- and AB+.
Blood Group Compatibility
The table below demonstrates blood type compatibility. A person with AB+ blood type can receive blood from all of the major blood type groups. At the other extreme people with O- blood type can only receive blood from donors with the same blood type.
Irish Blood Group Type Frequency Distribution
Blood group O Positive is the most common group in Ireland while AB negative is the least common.