And what that means is the red blood cells will have both of these antigens attached onto the membrane of the red blood cell. And this is what we call blood type AB. And because in this individual the red blood cell membrane contains both of these antigen types, our immune system will not produce antibodies against both of these types. And that's because the immune system will see antigen A and antigen B as self antigens. So these individuals with blood type AB do not have antibodies for either antigen A or antigen B. Now it is also possible that our individual doesn't have this gene on chromosome nine.