Is O Negative a Rare Blood Type?
Rhnull, the Golden Blood: Rarest Blood Type in the World
What's the Rarest Blood Type in Humans?
How many people in the world have Rh blood?
Blood is considered Rh-null if it lacks all of the 61 possible antigens in the Rh system.
The Rh blood group system is a.
Thus, notwithstanding it is a misnomer, the term survives e.