Blood phenotypes are based on the presence or absence of specific antigens on the surface of red blood cells. These antigens are inherited genetically and determine a person's blood type. The most common blood type system is the ABO system, which classifies blood into four main groups: A, B, AB, and O.
In addition to the ABO system, blood phenotypes are also determined by the Rh factor, which can be Rh positive or Rh negative. Combining the ABO and Rh factors gives us the eight main blood types: A+, A-, B+, B-, AB+, AB-, O+, O-.
Knowing a person's blood type is important for blood transfusions and organ transplants to ensure compatibility and avoid adverse reactions.
