Although most of the real world gets by quite peacefully with the more common blood types, in the world of entertainment only the rarest will do; if a character's blood type is mentioned, you can bet, if not your bottom dollar, then certainly one of the lower ones that it's going to be rare and special.
In the early twentieth century, red blood cells were first given the most common classifications: O, A, B and AB. Three decades later the Rhesus factor was also discovered, marking any blood as RH positive (+) or RH negative (-), and woe to you if you get a transfusion of the wrong RH. (Only applicable if the receiver is RH negative. In RH- blood there is no antigen for the RH+ body to recognize and fight, whereas the RH- body will attack RH+ blood.) Now, O red cells can be given to anyone, and AB can receive any type of red blood cells.
With plasma, it's the other way around. The plasma of group O people contains antibodies to both A and B blood group substances, which is why they have a reaction if they receive those types. So giving O plasma to an A patient may result in a minor reaction as the donated antibodies attack the recipient's cells. AB plasma has neither antibody, so it can be given to anyone.
Because plasma and red blood cells have opposite properties for donation and receiving, whole blood transfusions (rare except in the field with a direct donation) obviously require matching blood types to avoid reactions.
Blood in fiction really comes in only two types: universal donor (rare) and special needs (common), so that blood banks are overtaxed whenever the plot requires. In reality, even though AB- is the rarest blood type, it isn't all that hard to find a match for. Anybody with a Negative Rhesus blood type could donate to them in times of need.
In ideal medical conditions, doctors do prefer to match blood type as exactly as possible, especially when doing organ transplants to reduce the risk of rejection, but in a life-or-death situation - which is the only situation this trope would find worthwhile - any compatible blood type will do.
The situation of needing rare blood types is an actual problem that happens in medicine, but it is almost never ABO or Rh type and usually deals with other red cell antigens, most of which are rarely mentioned outside the blood banking community. Some of these are extremely rare or are only present in certain ethnic groups. According to The Other Wiki, there are two dozen factors.
By the way, how many of us actually know their blood types right off the top of their head? Everyone in fiction seems to know. This can be justified in some cases - Asians might be more curious due to their beliefs in Personality Blood Types. And in military oriented works due to many militaries including the information on the identification tags for their personnel. Blood donors will also usually know, having been told by the collection site at which they donated, and anybody who has had a blood donation should know. Women who are or have previously been pregnant often know, since the +/- factors in blood have a chance to cause catastrophic Rh incompatibility, potentially killing the developing child.
But for the guy on the street, it doesn't happen. You don't need to know your blood type, or keep that information on your person. No doctor would trust your information and risk a medical malpractice suit anyway.
You can thank Dr. Charles Drew for discovering and codifying blood types. He discovered how to match up blood types and also came up with a method for storing blood for up to 14 days (previously it was no good after 48 hours) saving thousands of lives in WWII.
Not to be confused with Did Not Do the Bloody Research.
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Anime & Manga
In general, many anime and manga series will list their characters' blood types in supplementary materials, due to the aforementioned Asian beliefs in Personality Blood Types. Given that something like 99% of people in Japan are Rh positive (+) the system is only based on the four antigen combinations. Functionally assume everyone is Rh positive unless specified to be otherwise.
Though it's only mentioned in supplemental materials, the fact that Mashiro in Mai-HiME has AB- blood in Japan, a country mostly without the negative RH factor, serves as an early clue that she's not quite what she appears to be. Plus she shares her blood type with Fumi, along with her birthday and voice actress.
Bombay blood type appears in Yakitate!! Japan, used to show that Pierrot Bolnez and the king of Monaco are related.
In Detective Conan, Conan's blood type is a major plot point during the Desperate Revival arc. Ran offers to donate blood to Conan, after he is shot earlier in the arc, without stopping to check his blood type, implying she knows he is Shinichi.
Eisuke Hondo is a universal donor. This is important because his sister, having donated blood to him, also had to be blood type O, meaning that she couldn't be Rena Mizunashi, who has blood type AB. Except, as it turns out, she is; Eisuke's blood type changed to AB when she donated some bone marrow to him due to his leukemia.
Word of God is that "Blood pattern Blue!" is a shoutout to an old Japanese scifi B-movie, in which people who see UFO's have their blood turn blue (then get discriminated against). It's an in-joke. Moreover they don't actually call it "Blood type" in the sense of AB- or O+, but "Blood Wave-Pattern" which is made up technobabble.
Like many anime series, the blood types of the main characters are listed in the supplementary materials, and fit the "blood type theory of personality" very accurately. Shinji is Type A, and is thus weak and submissive (a majority of people in Japan are actually Type A). Asuka is the only Type O, and accordingly is a hothead (it does make sense that as she is from Germany and the only non-Japanese person on the show, she has an uncommon blood type for Japan). Misato is even wounded in one episode and they display that her specific blood type she's getting in a transfusion is "AO", although there is no functional difference between "AA" and "AO" because A is dominant.
Rebuild of Evangelion complicates this further: an onscreen graphic notes that Unit-01 is BLUE A* while Sachiel is BLUE 04, being the fourth Angel in this continuity. Shamshel and Ramiel keeps this numbering too.
Ryouhei Sumi in Future GPX Cyber Formula 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, as it is difficult enough to use transfusion in case of an emergency—to the level that even though he got better, he gave up auto racing because of his blood type due to safety reasons.
In the 70's Shoujo horror/romance manga Akuma no Hanayome (Bride of Deimos), there's a story in the manga about the main character Minako's friend who was horribly disfigured in a car accident and Deimos made a deal to Minako that he can fix her friend's face if she agrees to marry him. She refuses his offer, so instead, she made a deal with the friend—who turns out to be a vampire, as she needed RH AB-Negative blood of young girls to keep her face from rotting once a month.
This is a significant plot point in One Piece, where Sanji is revealed to have a rare blood type, and Chopper runs out of spare blood for transfusions because Sanji keeps having incredible nose bleeds, prompting a crisis when the racist Fishmen refuse to donate blood.
This gets played about with a bit more later in the same arc, when Luffy is in dire need of a blood transfusion after fighting with Hody. No one else in the Straw Hats have the same blood type, but considering how small Luffy's crew is (and how one member doesn't even ''have'' blood, this is fairly believable. Several people in the nearby crowd do have the same blood type, and there has been blood loss at least a few times with it being dealt with offscreen, so it's implied to be not particularly rare; the Straw Hats just didn't have another ready source on hand at that particular moment.
Oh yes, and in One Piece, the blood types seen have been X,F,S,XF, and XFS.
One story in Black Jack features a rich businessman with a rare blood type. When he desperately needs a transfusion after an accident, he pays Black Jack a significant sum of money for help, and a construction worker is found who matches him. Several months later, the construction worker is himself injured. In order to help him, the businessman misses a vital plane flight and winds up losing his entire company. In the end, the best he can say is that at least he saved a life—until Black Jack gives him a check for most of the money he initially paid him.
The Bombay bloodtype is used in a case of Kindaichi Case Files as a clue to discover the killer and the town's dark secret. Despite being a rarity in Japan, at least 4 characters have this bloodtype.
In Hellsing, one Millennium vampire is shown identifying blood types by flavor like a wine connoisseur would identify a vintage. No vampires are shown suffering ill effects from drinking an incompatible blood type.
In A Certain Magical Index, as children, Vento of the Front and her brother were injured when an amusement park ride broke down. They both needed transfusions, but they both had Type-B RH negative. Since there were no donors on hand, Vento's brother told the doctors to give his remaining blood to her. Afterwards, Vento blamed the doctors for failing to save her brother, and developed a hatred of science.
In Hellblazer, Brendan Finn is "O Guinness positive", which makes him a "universal recipient". No, it's not magic, he just drinks a lot.
In the Yoko Tsuno album La Frontière de la Vie, the entire plot evolves from how a child has an exceedingly very rare blood.
In the infamous "I am Curious (Black)" Superman comic, Lois Lane turns black for a day (for a story on racism) and befriends a grassroots, er, community leader (it's never clarified what he is, he just stands on a soapbox, rants to a crowd, and later breaks up a drug deal), who hates him some crackers. When the man needs a blood transfusion, the doctor at the black hospital proclaims that the man is O-, but, horror of horrors, the hospital doesn't have enough money to carry all blood types! Luckily Lois, who has returned to her "white lady" status, is O-, and with the blood transfusion they bridge the gap of racism.
Diabolik is identified as AB- in the story The Bird of Prey. This is actually a plot point, as the sudden disappearance of five AB- blood donors is a clear warning that Diabolik is injured and needs blood (and, being a wanted criminal sentenced to death, going to the hospital would mean getting arrested, healed as required by the law and then executed). Ginko reacts by placing bugs on all the AB- blood donors, stopping Eva as she discovers it immediately, but it also causes a My God, What Have I Done? moment when he discovers why Eva kidnapped specifically AB- donors instead of compatible people: Diabolik had been victim of radiation poisoning that could be healed only with a full transfusion, requiring as much blood as five or six persons had, with Eva not being willing to take any risk. And, being unable to kidnap more people and take the standard donation doses, Eva exsanguinated the five donors she had kidnapped.
In the miniseries Hawkeye: Blindspot, the only clue Clint has to Trick Shot's killer is his blood type being A+. This trope is subverted, as the blood type really doesn't help much. Clint even lampshades that's his blood type. Eventually, this comes back to help him at the end, as it is revealed the killer, his brother Barney, is a perfect genetic match for a stem cell transplant that can save him from permanent blindness.
Films — Live Action
In the film Blood Work (based on a Michael Connelly novel), the FBI hero needs a heart transplant, but he has a rare blood type. So the serial killer bad guy, who likes it when the hero chases him, kills someone with that same blood type so the hero can get a matching heart.
Bruce Almighty sees Jennifer Aniston proudly declare herself to be AB+ , a "very rare blood type". This comes into play later in the film, when Bruce apparently has this type as well, as God sends him some of hers when he gets hit by a truck and needs a donation. It's some pretty awful research failure if you wanted to put any drama into it, since in reality Bruce could receive blood from anybody.
In an outtake, she declares herself to be AB negative, derailing the joke in the page quote.
The abducted victims in The X-Files: I Want to Believe all had AB- blood. It turns out that this is because the kidnapper is trying to perform a full-body transplant.
The Greatest Show on Earth, winner of the Academy Award for Best Picture in 1952, involves a train wreck with a victim that needs a blood transfusion. Guess what his blood type is? (And the fact that his AB- blood could accept a transfusion from ANY Rh negative donor is completely unknown to the doctor who is treating him. The donor has to be AB-, or nothing!)
Averted in Some Like It Hot, where it is reiterated that one of the main characters is a type O.
Averted in All The Young Men, a long-forgotten Korean War military drama featuring a young Sidney Poitier. His white CO needs a transfusion and is Type O, but they're all out of bottled O. Guess who else is Type O. This was considered daring in 1960.
Drives the plot in Made in America. The daughter learns her blood group in a biology class at school. She happens to know the blood group of her mother and her dead father and realises that she can't be her father's daughter. Whoopi Goldberg admits that in fact she wasn't pregnant when her partner died and used a sperm donor and pretended (even to herself) that it was her partner's child.
A major plot point of John Q. was that the title character's son was a rare bloodtype and needs a heart transplant. Meanwhile, a woman dies in a car wreck of the same bloodtype, and they eventually use her heart.
In Earthquake, a first responder at an aid station can be overheard pleading for an emergency shipment of AB- blood on a CB radio.
AB- figures in the plot of Robert A. Heinlein's I Will Fear No Evil, which involves the protagonist's brain being transplanted into a new body. Part of the plot setup is the rarity of the AB- blood type; the protagonist is shocked when his body donor was actually someone he knew well.
RAH himself was AB+, and a member of the National Rare Blood Club (which he mentions in an appendix to I Will Fear No Evil). To this day, sci fi conventions sponsor Robert A. Heinlein Memorial Blood Drives.
In Breaking Dawn The Cullens keep a refrigerator full of blood in their house. Naturally it's the very rare O-.
In An Echo In The Bone, one character, Ian, has it suggested that his wife's miscarriage was due to issues with their respective Rh blood types. (The ability to manage Time Travel intact is treated like a matter of genetics or blood type as well.)
Dracula, thanks to Science Marches On. When the book was written, the concept of blood transfusions was radical, cutting-edge science, and the possibility of an allergic reaction to someone else's blood wasn't known. Thus, Lucy can get transfusions from four different men without anyone worrying about blood type compatibility. Since she's in the process of becoming a vampire, blood types may be irrelevant to her in a very easy retcon. Another easy Fan Wank is to claim that Lucy's an AB blood type.
Everworld uses this trope correctly when the main characters have to give an emergency blood transfusion to Galahad. April volunteers because she's O-, the universal donor.
Invoked in a short story, Blood Money by Timothy O'Keefe, where a man with "a rare blood type" learns that his donation is being used by a vampire who can only digest that blood type.
Dorothy L. Sayers' short story Blood Sacrifice is based on another way of classifying blood types used in Britain in the early to mid twentieth century; how this translates to the modern system is unclear.
In the Joe Gunther novel Scent Of Evil, the fact that the person who left saliva on a cigarette left at the scene of a murder is is type AB, along with the brand of the cigarette, winds up implicating a member of the police force because it's such a rare type. The fact that the man is a secreter is also specifically called out as a bit of good luck since it allows them to identify his blood type through his saliva. The book was written in 1992, and actual DNA testing is not mentioned, but given how new the technology was at the time and the series being set in Vermont using an ABO system was much faster.
Live Action TV
Rare blood types always uncover parentage secrets on soap operas. All My Children 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 80's had Tina find her lost son because they both had Blood Type G.
All My Children even inverted this—when Dimitri learned that his presumed daughter Madeline was O-, he realized that she couldn't be his daughter because her common blood type was not possible, given his rare one.
On Dark Angel, Max, all of the other X5s, and most likely other transgenics as well, are specifically genetically programmed to have O- blood, so they could swap blood (and organs) on the battlefield. Also, the show makes the goof of a blood transfusion for Logan being difficult to find because he's AB-. Fortunately, universal donor Max was handy.
The title character of Dexter has a AB- as his bloodtype. It's shown in flashback that Dexter's foster father contacted Dexter's biological father when Dexter was injured and needed a blood transfusion, which falls into the Artistic License - Biology trope since in reality Dexter could have had any negative blood type given to him and been fine.
Good Times featured a rare blood type, U-, to facilitate a Who's on First? joke: "I have a very rare blood type, U Negative." "You positive?" "No, U Negative." And so forth.
House both lampshades the first and subverts the second. The subversion is something we expect from a medical show, while the lampshading comes later as House solves a case based on a patient's blood type (and a conversation with Wilson): the patient had blood type A, but when he was given a blood transfusion, was given the wrong type. Nobody ever thought to ASK him what his blood type even was to begin with. Then again, the fact that doctors do not ask patients their blood type is Truth in Television. (In the episode, the patient's Lupus caused a blood test to give the wrong result.) Many people don't know, some think they know but are wrong, and very very few people know that more than the ABO/Rh factors even exist, much less what they have. And that's assuming the patient is conscious and coherent.
In another episode, they play the trope straight. A woman in need of a liver transplant is apparently disadvantaged by having AB- blood. In fact, blood type would be the least of her worries.
LOST features a scene in which Jack struggles to find a donor for Boone and, failing to find a match among the other survivors, reveals himself to be O- and performs the transfusion using his own blood. He actually got Charlie to ask nearly everyone in the camp their blood type but only 4 people knew.
In "Journey to Babel", an episode of Star Trek: The Original Series, Ambassador Sarek requires open heart surgery which is hampered by his T- blood, noted as being rare, even for a Vulcan. Luckily, another person on board also had T- blood — Sarek's son, Spock, and that had to be filtered because of Spocks human heritage.
And since Vulcans have copper-based rather than Humans' iron-based blood, it's realistic that it would use a different blood type system.
The M*A*S*H episode in real-time, where Hawkeye and company are racing against the clock to save a soldier who, according to Winchester, has "that elusive type".
Normally averted on the show: All sorts of blood-types show up and they routinely run short of all of them.
The writers adapted the trope to make its use accurate and believable for the time period. It's never said that the soldier can only take AB- blood; it's stated (by Potter) that AB- blood would be the best for him. In the 50s it was thought that the more blood the patient had lost, the more important it was to provide the exact blood type.
They also had an episode about this. One wounded racist marine has a rare blood type and they tell him the only source is from a black soldier. They start applying makeup to make him darker and darker until he believes he's turning black. After they tell him he learns some tolerance.
Another common order given for patients who don't need to go into surgery right this damn second or they're going to die is "type and cross-match" so many units of blood. This directly tests the recipient's serum against the donor's blood cells, to verify that the recipient won't have any transfusion reaction from secondary antigens due to antibodies that might be present in his blood.
An early episode has a North Korean patient with a rare blood type needing a transfusion, and the only one in the entire camp with the same blood type is Frank. When the patient shows signs of hepatitis, Hilarity Ensues when Hawk and Trapper must keep him away from Hot Lips until his test results are in.
The Pretender: Jarod and Kyle both had AB- blood, along with a young boy from one episode who was in dire need of a heart transplant. Guess where that went.
(Sort of) averted on Angel, where when a vampire has refrigerated blood on hand, it is usually "O-neg".
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.
In Desperate Housewives, one of the characters began to suspect that another was their father because they both had AB- blood. Never mind that blood types don't actually work like this in real life (it's something to do with which factors you have and how they add together, he was far more likely to be A or B, and then positive simply because more people are positive and the positive genes are dominant, which is also why Rhesus negative women are more likely to have birth complications). It's also how Gabrielle ultimately learns that Juanita was Switched at Birth, which Carlos had tried to keep a secret from her.
On Moonlight, Beth Turner has "AO-" blood, which is especially tasty to vampires. While technically a real blood group, AO is just a rather pedantic way of giving one of the two genetic possibilities for type A blood.
The Hancock's Half Hour episode "The Blood Donor" is an iconic piece of British comedy. The Hancock character is nervous about giving blood at first but changes his mind when he discovers that his blood is AB- (although at one point the doctor tells him he is rhesus positive, causing him to remark "Rhesus? They're monkeys, aren't they?"). On returning home he pesters the hospital to make sure his blood is given to "the right sort of person", but then he injures himself, is rushed back to hospital and is given a transfusion of the blood he has just donated. Here We Go Again.
This is really Truth in Television given that the Rh factor is indeed named after the Rhesus monkey in which it was first discovered.
In Forever Knight, they actually not only get the blood type info right, saying Schanke, who is AB+ , "can take anything but motor oil," while O- can only receive O-, it's involved in a plot point, too. The killer's mother had died from hepatitis contracted from a blood transfusion, which slipped through the screening process; he was taking out only O- donors who could have been the source.
On Charmed, Piper has AB negative blood as does Andy. This is shown in the episode "The Wendigo". The Wendigo also attacks people with the AB negative blood type.
Piper: Yeah, I'm fine. If I pass out and I need a transfusion, I'm AB negative. It's very rare. It could be a problem. Andy: Uh, I was just thinking how I'm probably not the best cop to be on this stakeout with, seeing as how I'm, uh, AB negative. Andy: Maybe. I've just gone over the coroners reports from Chicago, New Orleans, and now local. It turns out all the victims were AB negative.
A third season episode of Chuck features Casey having to donate his AB- blood to save the life of a man he'd been trying to kill off and on for years (well, Chuck 'stole' it, but whatever).
In the last season of Queer as Folk, after the bombing in Babylon, Michael has been seriously hurt and taken to the hospital. The ER doctor says he needs a blood tranfusion, but he's AB negative and they are short on his type. Brian answers he's O negative, universal donor and wants them to take his blood. But they won't take it because he's gay and they are considered too high of a risk for HIV. Brian then goes berserk, but Ben tells him he couln't give his blood anyway because he had cancer. This is a reference to the Ban On Blood Donations From Gay Men in the USA implemented in 1985, and despite what the show says the policy 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). It was all just a convenient excuse for an Anviliciouslydramatic take on a real gay issue.
Comes up twice on The A-Team. The first time, B.A. needs a blood transfusion, type AB Negative. The only other member of the team with this blood type is Murdock. The second time, Murdock needs a transfusion. Guess.
Gossip Girl: Dan and Rufus Humphrey are both AB+. Milo, Georgina's and Dan's "son" is 0-.
In season five it turns out Chuck Bass has a super duper rare blood type (never specified which one) that means the only people in the whole wide world who could possibly give him blood are blood relatives. Which is how he ends up finding out his father is not quite as dead as we thought he was.
In The Sarah Connor Chronicles, 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 Bombay blood typenote 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. Sarah being unable to give blood to the AB- Derek Reese despite being a universal donor is correct due to compatibility for plasma being 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.
Another blend of this with Critical Research Failure appeared on Law and Order SVU, when a comatose woman's mysterious pregnancy is under investigation. Her blood type is A and the fetus's is AB, so the investigators conclude that its father must be type B ... even though a type AB father would also have a 50/50 chance of passing the B trait on to his child. Particularly deserving of a You Fail Genetics Forever is Huang, who agrees that the father's type must be B despite his own medical training.
And again on SVU, they assert that two type A parents must have a type A child. In real life there is a chance they could have a type O child.
True Blood. The (sorta) title drink has each blood type as a separate flavor, and vampires have preferences on their favorite. Newbie vamp Jessica drinks a cocktail of several different types to get used to the taste.
Vampires on the show also express preference for different "flavors" of real blood; Jessica orders room service in a hotel and a young man at the door introduces himself as "male, straight, B positive." Later, Erik offers another vampire "a human, AB negative, very rare."
One episode of Dad's Army was based around Pike being called up to join the regular army. The platoon can't get him out of it, so they hold a fish and chip supper to say goodbye to him - after which Pike announces that he was excused from joining the army because he has a very rare blood type, but didn't want to tell anyone until after the fish and chips.
The season-two finale of Monk featured a victim whose blood group was "AB-negative with a D-antigen—the rarest blood-type in the world!" It is indeed rare; in fact, it doesn't exist. This turned out to be why he was murdered — he was a death row inmate about to be executed, with his blood going to a local philanthropist in need of an operation. A prison employee had a grudge against the philanthropist and couldn't let that happen, so they poisoned the prisoner's last meal, making the blood worthless
Actually, Rh D isn't just Rh D - there are many, many subtypes, varying in their reactivity to anti-D1 from ever-so-slightly weaker than Rh D+ through to "Rh D? What Rh D?". Depending on the typing reagents, time and situation, it's not that unusual for weak D and partial D to mistype as Rh D-.
Psych actually did the research in an episode. When a man needed O negative donations, Lassiter had the needed bloodtype.
In a variant on CSI: Crime Scene Investigation, a power outage shuts down the lab's equipment, and the investigators must resort to old-school ABO typing of blood evidence. Greg remarks that he's got clumping in his Type O sample; this is an error, as Type O is distinguished as such by its failure to clump when exposed to anti-A or anti-B serum. (It could've been O-positive and clumped in anti-Rh serum, but Rh-typing wasn't otherwise mentioned.)
In the Ever Decreasing Circles episode "A Strange Woman", Paul (Peter Egan) is taken away in a police car in the middle of the night. The following day, he explains that he is a registered blood donor and has a rare (yet unspecified) blood type and had to be rushed to the hospital to donate to an accident victim. His neighbour and self-perceived rival Martin (Richard Briers) promptly registers as a blood donor, and is disappointed to learn that he has Type O blood.
Twin Peaks: In the first episode of the second season, the blood of the killer later revealed to be Leland is said to be " a rare type, AB Negative"
Bay in Switched at Birth has AB blood, though she doesn't mention her Rh factor. This is a clue to her parentage, since both her parents are type A. (Type AB requires inheriting an A from one parent and a B from the other. A child of two type As can only be type A or type O.)
Due Southinverts it in one episode, when an over-eager FBI agent excitedly declares that they now know the suspect's blood type. Fraser points out that the suspect's blood type is shared by a significant portion of the population of Chicago.
In "Anslo Garrick" (Part 1) of The Blacklist, it is revealed that both Red and Ressler share the same blood type (B-), which came in handy since Red needs to give Ressler an immediate blood transfusion to help him recover after having been shot in the leg.
In Person of Interest, Shaw is AB+, which allows her to accept blood from anyone. She takes advantage of this in one episode after being wounded by taking a Russian mobster prisoner and stealing his blood for a transfusion.
In Victorious, Robbie is about to have a surgery, but needs O- blood. Tori is the only one of their friends who has this blood type, but is about to star in a play. After Tori donates a pint of blood, the doctors end up losing it, and after donating another pint, Robbie ends up dropping it on the floor, forcing her to donate a third pint. Tori then becomes weak and disoriented during the play.
In Major Crimes, during their investigation, the team discovers that the father that was missing had AB type blood, which means he couldn't have fathered his type O daughter.
German singer Udo Lindenberg once made the song "0 rhesus negativ" where he meets a vampire, but is spared because the vampire can't stand that special blood type.
In the middle school musical Dracula, Baby Dracula offers to do anything in his power to help Lucy. He is asked if he's type B (Lucy's type) or O - the universal donor. He replies that he's type AB - the universal receiver.
Shadow Hearts: Covenant has a door in one dungeon that will only open if a person with AB blood tries to open it; this was done by its builder to ensure her apprentice, the party member Lucia, wouldn't get into things she shouldn't. Only one member of your party can open it, leading to a brief puzzle to determine which of your party members is AB. Oddly enough, it isn't Yuri (type A) or Karin (also type A), the main characters — it's Gepetto. Joachim is type O and Lucia is type B.
Toko in Kara no Shoujo is of the Bombay blood group which means that she can't get a blood transfusion after getting hit by a truck.
In Dead Island all four of the virus-immune survivors have O negative blood. This is presumably not a coincidence, although it is never really explored.
In Darths and Droids, Qui-Gon's player has his character's blood type written on his character sheet. It's O- making him a universal donor, however he actually wanted AB+ to make the character more capable of receiving medical treatment, but didn't know that there was a difference, and the type he picked would only be useful if he just needed blood plasma. Pete brings up that a universal recipient would be preferable, but he's also the Munchkin of the group.
King of the Hill sees Peggy bragging to neighbour Minh about how she has blood of type AB- and giving this trope its name.
Mihn: I'm type O. Universal donor.
Peggy: Oh, yeah? Well I have the rarest blood of all; AB Negative! Liquid Gold!
The Simpsons second season episode "Blood Feud," Mr. Burns needs a OO- transplant, and Bart is the only person in town with the same blood type. He uses it as a bargaining chip. While it is correctly described as rare, its rarity is greatly exaggerated.
They make a point of it being double-O negative, not just O-neg. It may be a case of fictionalized blood type.
In South Park, it is revealed that Kyle and Cartman are the only two people in town with AB- blood... leading to some problems when Kyle needs a kidney transplant and Cartman won't let him have it.
An episode of Courage the Cowardly Dog has a government agency capture Muriel because she was one of the three or so people on the planet with the blood type "ABXYZ."
The plot of Batman & Mr. Freeze: SubZero involves Mr. Freeze kidnapping Barbara Gordon because she shares the AB- blood type with his wife. Barbara even brings up that he could use any negative blood for a blood transfusion, but it turns out that he needs more than just her blood. Truth in Television in that organ transplants are ideally done between people of the same blood type to reduce the risk of rejection, and Mr. Freeze is obsessive enough over getting his wife back that he'd try to be as exact as possible.
In the Young Justice episode "Image", a young boy named Garfield Logan is caught in an explosion and is badly injured. Dying from his injuries, he needed a transfusion of type O blood to live, of which the isolated farm's supplies were just destroyed. Nobody on site has type O blood, except Miss Martian, who can shapeshift her body to the cellular level. The transfusion will later give the character shapeshifting powers and he reappears in season 2 as Beast Boy.
In the Highlander animated series, it is mentioned in one episode that all Immortals are universal blood donors (O-). This is used in that episode as an explanation as to why Quentin's blood can save a wounded mortal's life, then never gets mentioned again.
In the Super Friends episode "A Pint of Life", a young boy is injured in an accident. He needs a transfusion, but his blood type is so rare that the only possible donor they can think of is his father. Since his father is currently exploring the Amazon Rainforest, the Super Friends have to retrieve him.
Truth In Television
Bombay Type blood is an extremely rare blood type that cannot accept any ABO-normal blood. Genetically they may have any of the normal ABO types, but they test as type O due to a lack of H antigen, which is present in ABO-normal people (type O only has H; in A, B and AB the H acts as an anchor for the additional antigens). They will have a hemolytic reaction if given O negative (which is otherwise considered the universal donor for blood) and must be given Bombay (Oh) blood. For this reason when a blood bank receives a Bombay donation, they never discard it as they do with other blood types after a certain period or expiration date. It's named after the city in which it was discovered, and people who have it are mostly concentrated in that region of India (even there, they're a minority), and practically nowhere else in the world.
Patients with active systemic lupus erythematosus (SLE) sometimes become intolerant of their own ABO/Rh blood type, as their overly-picky immune systems launch attacks against even their own blood cells. A perfect cross-match is essential before such patients receive a transfusion, and the blood itself must be infused slowly and at body temperature to minimize any risk of reaction.
In Japan, one's blood type is considered important. Having AB- blood apparently marks one out as, essentially, a Byronic Hero (destined for leadership, intelligent, magnetic personality but prone to arrogance and poor self-control). Given that John F. Kennedy and Marilyn Monroe were AB-, perhaps they are on to something.