[Born Conservative]

I don’t know if this will do anything to change the Rh factor, but at least they can convert A, B, and AB negative to O negative blood. O neg can be given to any blood type, as well as to those with negative and positive Rh.

[Myrddin]

It's nice the A/B/O is solved. It doesn't fix Rh. There are actually 20 antigen groups.

[PJ-Comix]

I’ve got O negative. Nice to know I have such WANTED blood.