# What's your blood type? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [November 19, 2010, 3:15am UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187 "2010-11-19T03:15:13Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Galileo](https://avatars.discourse-cdn.com/v4/letter/g/85e7bf/32.png) [@Galileo](https://boards.straightdope.com/u/Galileo)\ **Post date:** [November 19, 2010, 12:36pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/21 "2010-11-19T12:36:15Z")
> [@Zsofia](#): > > the damned Red Cross won’t leave me alone > [@spooje](#): > > Once the Red Cross finds out, you are a marked man (or woman). What does that mean? What does the Red Cross do when they find out your blood type? I don’t know what my blood type is. How do people know? Is it on your birth certificate? It’s not on mine. I know that you can find out your blood type when you donate but, when I tried donating years ago, I was refused for medical reasons. ---
**Author:** ![KarlGrenze](https://avatars.discourse-cdn.com/v4/letter/k/dbc845/32.png) [@KarlGrenze](https://boards.straightdope.com/u/KarlGrenze)\ **Post date:** [November 19, 2010, 12:36pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/22 "2010-11-19T12:36:17Z")
A-, and found that out when I was 19 and donated whole blood for the first time. Confused the hell out of my parents for a little while, since they are both confirmed A+. Turns out, both of my grandfathers are A-. And my parents got their 1 in 4 chance on the first and only try. ---
**Author:** ![KarlGrenze](https://avatars.discourse-cdn.com/v4/letter/k/dbc845/32.png) [@KarlGrenze](https://boards.straightdope.com/u/KarlGrenze)\ **Post date:** [November 19, 2010, 12:40pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/23 "2010-11-19T12:40:51Z")
> [@Galileo](#): > > What does that mean? What does the Red Cross do when they find out your blood type? If there is a blood shortage in your area, and it’s of your type, or a type you could donate to, they’ll call you to remind you to donate, please. > [@](#): > > I don’t know what my blood type is. How do people know? Is it on your birth certificate? It’s not on mine. You could donate and found out when donating. The basic tests are not that difficult to do. I had one of them done before one of my donations, many years ago. It’s not on the birth certificate, no. Also, if you go to the hospital and are likely to be a candidate for blood transfusion, they’ll of course type your blood, to make sure you get the right one. Even if they don’t tell you, you can ask. ---
**Author:** ![Turek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/turek/32/18782_2.png) [@Turek](https://boards.straightdope.com/u/Turek)\ **Post date:** [November 19, 2010, 1:17pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/24 "2010-11-19T13:17:16Z")
I’m the only person I know with an ironic blood type: B+. I’m actually quite cynical. 😉 ---
**Author:** ![Scubaqueen](https://avatars.discourse-cdn.com/v4/letter/s/c0e974/32.png) [@Scubaqueen](https://boards.straightdope.com/u/Scubaqueen)\ **Post date:** [November 19, 2010, 1:59pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/25 "2010-11-19T13:59:21Z")
> [@spooje](#): > > I’m O- as well. It’s the duct tape of blood. Anyone can use it in a pinch. Once the Red Cross finds out, you are a marked man (or woman). tell me about it. i’m bneg which is the second rarest. i got a tattoo for my birthday some years ago, and of course you can’t give blood for a year afterward. to the very day the moratorium on me ended - the blood center called me to come donate. 😛 ---
**Author:** ![IvoryTowerDenizen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ivorytowerdenizen/32/17937_2.png) [@IvoryTowerDenizen](https://boards.straightdope.com/u/IvoryTowerDenizen)\ **Post date:** [November 19, 2010, 2:06pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/26 "2010-11-19T14:06:53Z")
A+ My blood type, but sadly, not my GPA. ---
**Author:** ![Sigmagirl](https://avatars.discourse-cdn.com/v4/letter/s/c89c15/32.png) [@Sigmagirl](https://boards.straightdope.com/u/Sigmagirl)\ **Post date:** [November 19, 2010, 2:26pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/27 "2010-11-19T14:26:55Z")
O- with no anti-CMV antibodies. They like me a lot. ---
**Author:** ![Antigen](https://avatars.discourse-cdn.com/v4/letter/a/848f3c/32.png) [@Antigen](https://boards.straightdope.com/u/Antigen)\ **Post date:** [November 19, 2010, 2:27pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/28 "2010-11-19T14:27:01Z")
> [@Galileo](#): > > What does that mean? What does the Red Cross do when they find out your blood type? > > I don’t know what my blood type is. How do people know? Is it on your birth certificate? It’s not on mine. As mentioned already, you can get typed when you donate blood, or when you’re in the hospital with a chance of needing a transfusion, or if you’re a pregnant woman. Some babies get typed at birth depending on their mother’s type, because an incompatibility can cause problems. Normally you’ll only be tested for ABO type (and all the nasty bloodborne pathogens) and it’ll stop there. But when a patient has antibodies against [other red cell antigens](http://en.wikipedia.org/wiki/Human_blood_group_systems#Blood_group_systems), we need to find blood negative for those specific things, so we’ll pull units from the shelf and start testing. If the red cross, in the course of this testing, finds that you’re negative for something that almost everyone else is positive for, or negative for a rare combination of things, you can bet your butt they’ll make a note of it and try to have you donate more. They have a rare donor registry where they keep files of people who have one-in-a-million blood antigen patterns, because sometimes it can take days to find a suitable unit for a patient if they’ve got antibodies to very common things - because everyone’s blood will be positive for it. There are also “special” units that are kept frozen in reference labs for cases like this. Blood is awesome. Did you know that some type A people can’t just get type A blood? Some people are a _subgroup_ of A called A2, and they can make antibodies against the regular prevalent A1, so you need to either type a bunch of units to find a donor who’s also that subgroup, or just give them type O. Oh, and here’s the American Red Cross [donor eligibility info](http://www.redcrossblood.org/donating-blood/eligibility-requirements/eligibility-criteria-topic), in case anyone’s interested. ---
**Author:** ![bouv](https://avatars.discourse-cdn.com/v4/letter/b/bc8723/32.png) [@bouv](https://boards.straightdope.com/u/bouv)\ **Post date:** [November 19, 2010, 2:35pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/29 "2010-11-19T14:35:04Z")
I’m O-. I feel like we get the biggest shaft. Give to everybody, but can only take our own…I hate those damn AB+ moochers! ---
**Author:** ![One\_And\_Only\_Wanderers](https://avatars.discourse-cdn.com/v4/letter/o/838e76/32.png) [@One\_And\_Only\_Wanderers](https://boards.straightdope.com/u/One_And_Only_Wanderers)\ **Post date:** [November 19, 2010, 2:38pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/30 "2010-11-19T14:38:42Z")
> [@bouv](#): > > I’m O-. I feel like we get the biggest shaft. Give to everybody, but can only take our own…I hate those damn AB+ moochers! Wait till you need some plasma pal! Who’s universal now? 😉 ---
**Author:** ![Bam\_Boo\_Gut](https://avatars.discourse-cdn.com/v4/letter/b/8c91f0/32.png) [@Bam\_Boo\_Gut](https://boards.straightdope.com/u/Bam_Boo_Gut)\ **Post date:** [November 19, 2010, 3:10pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/31 "2010-11-19T15:10:06Z")
A+ here. I live on a small island pop. 80,000. My O friends are hounded. I walked in on one friend on the phone “Find someone else, I’m hungover and I haven’t eaten yet” She did crawl in later in the day. ---
**Author:** ![Snickers](https://avatars.discourse-cdn.com/v4/letter/s/5daacb/32.png) [@Snickers](https://boards.straightdope.com/u/Snickers)\ **Post date:** [November 19, 2010, 3:22pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/32 "2010-11-19T15:22:41Z")
O-. The vampires at the various blood banks are always hounding me. ---
**Author:** ![IvoryTowerDenizen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ivorytowerdenizen/32/17937_2.png) [@IvoryTowerDenizen](https://boards.straightdope.com/u/IvoryTowerDenizen)\ **Post date:** [November 19, 2010, 3:23pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/33 "2010-11-19T15:23:06Z")
> [@Bam\_Boo\_Gut](#): > > A+ here. I live on a small island pop. 80,000. My O friends are hounded. I walked in on one friend on the phone “Find someone else, I’m hungover and I haven’t eaten yet” She did crawl in later in the day. Reading quickly, I read this as “My O friends are haunted”. Oh my! :eek: ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [November 19, 2010, 5:55pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/34 "2010-11-19T17:55:01Z")
> [@KarlGrenze](#): > > If there is a blood shortage in your area, and it’s of your type, or a type you could donate to, they’ll call you to remind you to donate, please. Oh, if only that were all. If they just called me to say, “Hi, there’s a serious shortage and we’d really like you to come in!” or even “There’s always need for blood over the holidays - could you make an appointment?” that would be fine. It’s all the damned TIME, though, several times a week. ---
**Author:** ![JuliaSqueezer](https://avatars.discourse-cdn.com/v4/letter/j/82dd89/32.png) [@JuliaSqueezer](https://boards.straightdope.com/u/JuliaSqueezer)\ **Post date:** [November 19, 2010, 6:39pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/35 "2010-11-19T18:39:55Z")
> [@Sigmagirl](#): > > O- with no anti-CMV antibodies. They like me a lot. Heyyyy! Me too! The Red Cross has me on speed-dial! I’ve donated several gallons so far and I am irrationally proud of my collection of those little red drop tie tacks, even though I do not wear neckties. A recent problem seems to be a buildup of scar tissue in my arms from some “bad sticks” by the nurses, so I will be slowing down (if not halting altogether) my donations. ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [November 19, 2010, 6:42pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/36 "2010-11-19T18:42:19Z")
Great post-to-user-name match there. ---
**Author:** ![alphaboi867](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alphaboi867/32/3898_2.png) [@alphaboi867](https://boards.straightdope.com/u/alphaboi867)\ **Post date:** [November 19, 2010, 6:56pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/37 "2010-11-19T18:56:06Z")
> [@Galileo](#): > > …I don’t know what my blood type is. How do people know? Is it on your birth certificate? It’s not on mine… I found out when I was 15 and needed a physical to go overseas with People to People. A- ---
**Author:** ![LavenderBlue](https://avatars.discourse-cdn.com/v4/letter/l/e95f7d/32.png) [@LavenderBlue](https://boards.straightdope.com/u/LavenderBlue)\ **Post date:** [November 19, 2010, 6:59pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/38 "2010-11-19T18:59:30Z")
Does the prevalence of blood types vary from population to population? Are there any known populations where AB- might be far more common? Just curious. Thanks. ---
**Author:** ![Inigo\_Montoya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/inigo_montoya/32/124_2.png) [@Inigo\_Montoya](https://boards.straightdope.com/u/Inigo_Montoya)\ **Post date:** [November 19, 2010, 7:16pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/39 "2010-11-19T19:16:59Z")
AB+ ---
**Author:** ![The\_Flying\_Dutchman](https://avatars.discourse-cdn.com/v4/letter/t/9fc348/32.png) [@The\_Flying\_Dutchman](https://boards.straightdope.com/u/The_Flying_Dutchman)\ **Post date:** [November 19, 2010, 7:23pm UTC](https://boards.straightdope.com/t/whats-your-blood-type/561187/40 "2010-11-19T19:23:51Z")
> [@Antigen](#): > > I’m a mutant! Or a chimera. [Previous page](https://boards.straightdope.com/t/whats-your-blood-type/561187.md?page=1) [Next page](https://boards.straightdope.com/t/whats-your-blood-type/561187.md?page=3)