Blood types
Disease Information
Overview
A person can have one of four possible blood types (O, A, B and AB) and an Rh (Rhesus) factor, which is either positive or negative. Together, they mean that a person's blood has certain proteins. Blood type refers to proteins on red blood cells and in body fluids and the Rh factor refers to a protein found on the covering of the red blood cells. A person is Rh positive if the protein is present and Rh negative if the protein is absent.
There are eight possible blood type/Rh combinations:
|
Blood Type |
A |
B |
O |
AB |
|---|---|---|---|---|
|
Rh positive |
A+ |
B+ |
O+ |
AB+ |
|
Rh negative |
A- |
B- |
O- |
AB- |
