AB negative blood type
The rarest of the eight main blood types: fewer than 1 in 100 Americans is AB negative.
0.6%
about 1 in 167 people · #8 of 8
What AB negative means
AB negative red cells carry A and B antigens but no Rh D. The plasma has no anti-A or anti-B.
AB negative patients can receive red cells from all four Rh-negative types: AB−, A−, B− and O−.
It is the rarest combination because it needs both the A and B alleles plus two copies of the Rh-negative allele.
Plasma
AB- plasma can be given to O+, O-, A+, A-, B+, B-, AB+, AB-. A AB- patient can receive plasma from AB+, AB-. Plasma rules run opposite to red cells because plasma carries antibodies, not antigens.
Best way to donate
Plasma. AB negative plasma, like all AB plasma, can go to any patient. AB negative red cells help AB− and AB+ patients.
Genetics
ABO genotype AB; Rh genotype dd. Want to know what blood type your children could have? Use the blood type calculator.
Pregnancy
Rh negative: anti-D (RhoGAM) is usually offered if the baby could be Rh positive. Read the Rh factor guide.
AB negative blood type FAQs
Who can AB negative donate to?
AB− and AB+ red cells; plasma to any type.
Who can AB negative receive from?
AB−, A−, B− and O− red cells.
Is AB negative the rarest blood type?
Among the eight standard types, yes. Much rarer blood exists outside the ABO/Rh system, such as Rh-null and the Bombay phenotype.