History Main / ABNegative

* The abducted victims in ''{{The X-Files}}: I Want To Believe'' all had AB- blood.

** This troper finds it funnier that she states this in the context of the blood type being important for donation as the only type she can donate to is ''another'' AB+

* ''{{Terminator}}: TheSarahConnorChronicles'' combined this trope with DidNotDoTheResearch when they mentioned that Sarah had O- blood but John had AB- blood; this would mean that she couldn't possibly be his mother, barring vanishingly rare situations like mutation or [[http://en.wikipedia.org/wiki/Hh_antigen_system Bombay blood type]][[hottip:For the record, type O is recessive, and Sarah is therefore by necessity homozygous for O. Johny could be AO (type A) or BO (type B), but type AB is not possible]]. Note that Sarah being unable to give blood to the AB- Derek Reese despite being a universal donor could be correct, since she's giving whole blood containing plasma, not just blood cells, and compatibility for plasma is reversed compared to blood cells -- someone with type O is the least useful donor because their plasma could contain antibodies against non-O blood types.

* ''{{Terminator}}: TheSarahConnorChronicles'' combined this trope with DidNotDoTheResearch when they mentioned that Sarah had O- blood but John had AB- blood; this would mean that she couldn't possibly be his mother, barring vanishingly rare situations like mutation or [[http://en.wikipedia.org/wiki/Hh_antigen_system Bombay blood type]][[hottip: For the record, type O is recessive, and Sarah is therefore by necessity homozygous for O. Johny could be AO (type A) or BO (type B), but type AB is not possible]]. Note that Sarah being unable to give blood to the AB- Derek Reese despite being a universal donor could be correct, since she's giving whole blood containing plasma, not just blood cells, and compatibility for plasma is reversed compared to blood cells -- someone with type O is the least useful donor because their plasma could contain antibodies against non-O blood types.

* ''{{Terminator}}: TheSarahConnorChronicles'' combined this trope with DidNotDoTheResearch when they mentioned that Sarah had O- blood but John had AB- blood; this would mean that she couldn't possibly be his mother, barring vanishingly rare situations like mutation or [[http://en.wikipedia.org/wiki/Hh_antigen_system Bombay blood type]]. Note that Sarah being unable to give blood to the AB- Derek Reese despite being a universal donor could be correct, since she's giving whole blood containing plasma, not just blood cells, and compatibility for plasma is reversed compared to blood cells -- someone with type O is the least useful donor because their plasma could contain antibodies against non-O blood types.

** Why does this bar Sarah from being his mother? If John got an O- allele from his mother, and an AB- allele from his father, then he would have AB- blood. O- is recessive.
** For her to be O she'd have to be homozygous OO. To be A you can have one A allele and one O allele, or two A alleles (as O is recessive, Likewise for B), but to be AB you have to have one A allele and one B allele. Even if the father was AB she could only have kids who were either A OR B, as they would all have an O allele from her.

** Maybe AA has too much of the A taste?

* Ryouhei Sumi in ''FutureGPXCyberFormula'' once gets into an accident which caused some serious loss of blood in one filler episode. His blood type (AB) is not shown, but is mentioned to be very rare.

* Angels in NeonGenesisEvangelion must be identified on the computers as having [[TechnoBabble Blood Type BLUE]] before the [[HumongousMecha Evas]] can attack them. The fact that the majority of Angels are several stories tall and [[FrickinLaserBeams shoot lasers]] isn't enough of a giveaway.

* Ryouhei Sumi in ''FutureGPXCyberFormula'' once gets into an accident which caused serious lost of blood in one filler episode. His blood type (AB) is not shown, but is mentioned to be very rare.

* Ryouhei Sumi in FutureGPXCyberFormula once gets into an accident causing him serious lost of blood in one filler episode. His blood type is not shown, but is mentioned to be very rare.

In reality, blood comes in four types: O, A, B and AB. It has two attributes, RH positive (+ ) and RH negative (-), and woe to you if you get a transfusion of the wrong RH (which would be getting RH+ if you're RH-). Now, O can be given to anyone, and AB can receive any blood type. So a really rare blood type for receiving a donation would be B-, then A-, possibly followed by O- (because the only type they can tolerate is another O-).

** And again on ''SVU'', they assert that two type A parents must have a type A child (the child could also be type O). And then, after learning the supposed daughter is type B, they assert that the mother could not possibly be her mother.
*** That last part is completely true. It's physically impossible for two type A parents to have a type B child, regardless of whether their alleles are homogenous or heterogenous. What are you complaining about there?

* Angels in NeonGenesisEvangelion must be identified on the computers as having [[TechnoBabble Blood Type BLUE]] before the [[HumongousMecha Evas]] can attack them. The fact that the majority of Angels are several stories tall and shoot [[FrickinLaserBeams lasers]] isn't enough of a giveaway.

* Angels in NeonGenesisEvangelion must be identified on the computers as having [[{{Technobabble}} Blood Type BLUE]] before the [[HumongousMecha Evas]] can attack them. The fact that the majority of Angels are several stories tall and shoot [[FrickinLaserBeams lasers]] isn't enough of a giveaway.

* Angels in NeonGenesisEvangelion must be identified on the computers as having [[technobabble Blood Type BLUE]] before the [[HumongousMecha Evas]] can attack them. The fact that the majority of Angels are several stories tall and shoot [[FrickinLaserBeams lasers]] isn't enough of a giveaway.

* Angels in NeonGenesisEvangelion must be identified on the computers as having Blood Type BLUE before the [[HumongousMecha Evas]] can attack them. The fact that the majority of Angels are several stories tall and shoot lasers isn't enough of a giveaway.

** The policy actually isn't as set-in-stone as many media outlets make it seem. Doctors at hospitals are desperate for any compatible blood type in a pinch, and in real life they more than likely wouldn't turn Brian away if he were on the scene. It's only at blood drives that they screen for gay men (which is still horrible, but my original point stands). And besides, as a type AB- Michael could accept ''any'' blood type with a negative Rh, so the likelihood that the hospital was short on ''every'' negative blood type is just a convenient excuse for an {{Anvilicious}} take on a related gay issue.

** The policy actually isn't as set-in-stone as many media outlets make it seem. Doctors at hospitals are desperate for any compatible blood type in a pinch, and in real life they more than likely wouldn't turn Brian away if he were on the scene. It's only at blood drives that they screen for gay men (which is still horrible, but my original point stands). And besides, as a type AB- Michael could accept ''any'' blood type with a negative Rh, so the likelihood that the hospital was short on ''every'' negative blood type is just a convenient excuse for a [[{{Anvilicious}} sufficiently]] [[RuleOfDrama dramatic]] take on a gay issue.

* Rare blood types always uncover parentage secrets on soap operas. ''AllMyChildren'' used it a few years ago to reveal that Jack was Greenlee's father, though the rare blood type was never named. Much worse, ''{{One Life to Live}}'' back in the 80s had Tina find her lost son because they both had Blood Type G.

* ''TrueBlood''. It is implied that the differnt blood types taste different to the undead.

* ''{{Oz}}''. When a prison guard is stabbed in the eyes and needs a blood transfusion, the only donor immediately available is inmate Ryan O'Reilly, who makes it a condition of his helping that his mentally-ill brother be moved into Em City with him. Unit Manager Tim [=McManus=] had earlier refused to do this unless Ryan confessed to arranging the [[MurderTheHypotenuse murder of Dr Nathan's husband]], so it appears that he's lost this bargaining chip. Ryan, it turns out, confesses anyway in a rare moment of remorse.