# AB+ blood type **URL:** \ **Category:** Factual Questions\ **Created:** [May 30, 2012, 5:03pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557 "2012-05-30T17:03:29Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![zameria](https://avatars.discourse-cdn.com/v4/letter/z/96bed5/32.png) [@zameria](https://boards.straightdope.com/u/zameria)\ **Post date:** [May 30, 2012, 5:03pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/1 "2012-05-30T17:03:29Z")
My question is this…my younger brother who just passed away and was an organ donor had AB+ blood, whereas, my Father was O+ and my Mother is O-…is this possible? Or is it true about the mailman scenario??? ---
**Author:** ![VOW](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/vow/32/3043_2.png) [@VOW](https://boards.straightdope.com/u/VOW)\ **Post date:** [May 30, 2012, 5:05pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/2 "2012-05-30T17:05:49Z")
If both your parents were Type O, I’d say your brother was adopted. Type O is recessive, which means your parents each had “OO.” Your brother HAD to get “A” from one biological parent and “B” from the other one. ~VOW ---
**Author:** ![colonial](https://avatars.discourse-cdn.com/v4/letter/c/34f0e0/32.png) [@colonial](https://boards.straightdope.com/u/colonial)\ **Post date:** [May 30, 2012, 5:18pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/3 "2012-05-30T17:18:41Z")
> [@zameria](#): > > My question is this…my younger brother who just passed away and was an organ donor had AB+ blood, whereas, my Father was O+ and my Mother is O-…is this possible? Or is it true about the mailman scenario??? Something is fishy here, but not the mailman. It is impossible for a type O parent to have a type AB child, regardless of the other parent’s blood type; see link: [Blood Types and Parentage](http://www.bloodbook.com/inherited.html) ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [May 30, 2012, 5:41pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/4 "2012-05-30T17:41:35Z")
There is a rare genetic condition known as the Bombay blood group which sort of “masks” the ABO system, so that people with the condition test as type O, regardless of what their actual blood type is. However, it’s very rare, and in this case, both parents would need to have it without passing it on to their son, so it’s far more likely that either: -the son was adopted -one or more of the three reported blood types was incorrect ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [May 30, 2012, 5:46pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/5 "2012-05-30T17:46:35Z")
^ What smeghead said. I’m guessing misreporting of type is most likely, but it’s not unheard of for a child to be adopted and he and siblings unaware of that fact. ---
**Author:** ![gkster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gkster/32/14107_2.png) [@gkster](https://boards.straightdope.com/u/gkster)\ **Post date:** [May 30, 2012, 5:55pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/6 "2012-05-30T17:55:40Z")
Not to be intrusive, but would knowing the OP’s own blood type be relevant to finding out more about the situation? ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [May 30, 2012, 7:49pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/7 "2012-05-30T19:49:26Z")
“Alice, how come Charlie doesn’t look at all like our other three kids? Who’s his real father!??” “Why, you are, dear.” I thought O could donate to AB in some circumstances. Are you sure this was not the case, that he was O as well? It’s not a paternity malfunction, because both parents would have to be either A or B or AB. ---
**Author:** ![VOW](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/vow/32/3043_2.png) [@VOW](https://boards.straightdope.com/u/VOW)\ **Post date:** [May 30, 2012, 8:02pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/8 "2012-05-30T20:02:51Z")
> [@md2000](#): > > “Alice, how come Charlie doesn’t look at all like our other three kids? Who’s his real father!??” > “Why, you are, dear.” “Actually, Charlie doesn’t look much like either one of us…” ~VOW ---
**Author:** ![Annie-Xmas](https://avatars.discourse-cdn.com/v4/letter/a/ecc23a/32.png) [@Annie-Xmas](https://boards.straightdope.com/u/Annie-Xmas)\ **Post date:** [May 30, 2012, 8:04pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/9 "2012-05-30T20:04:07Z")
O can donate to AB or any other blood type in _all_ circumstances; it’s the universal donor. AB is the universal receipant. O can only receive from O, and AB can only donate to AB. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [May 30, 2012, 8:06pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/10 "2012-05-30T20:06:23Z")
> [@Annie-Xmas](#): > > O can donate to AB or any other blood type in _all_ circumstances; it’s the universal donor. AB is the universal receipant. > > O can only receive from O, and AB can only donate to AB. I thought O negative was the universal donor. Wouldn’t the antigens in O positive present problems in a donation? ---
**Author:** ![mnemosyne](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)\ **Post date:** [May 30, 2012, 8:42pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/11 "2012-05-30T20:42:36Z")
The Rhesus factor (the positive/negative when referencing blood groups) is rather easily removed from whole blood for donation, so it’s rarely an issue. That said, yes, O negative more worthy of the “universal donor” name than the positive. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [May 30, 2012, 9:00pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/12 "2012-05-30T21:00:49Z")
> [@mnemosyne](#): > > The Rhesus factor (the positive/negative when referencing blood groups) is rather easily removed from whole blood for donation, so it’s rarely an issue. How so? I assume you mean simply by using Rh- blood (which is quite different than “removing” the antigen is question). ---
**Author:** ![Apollyon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/apollyon/32/4238_2.png) [@Apollyon](https://boards.straightdope.com/u/Apollyon)\ **Post date:** [May 30, 2012, 10:13pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/13 "2012-05-30T22:13:42Z")
> [@pulykamell](#): > > I thought O negative was the universal donor. Wouldn’t the antigens in O positive present problems in a donation? Yes, O- is the universal donor, and AB+ is the universal recipient (at least when only considering ABO and Rhesus). “A pint of your best barman!” 🙂 – Apollyon, AB+ ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [May 30, 2012, 10:31pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/14 "2012-05-30T22:31:57Z")
It seems awfully unlikely, but impossible? A geneticist once explained to me how two type O parents could have a type A child. I’ll explain in a second, but let me say that the likelihood of an AB child would seem to be the square of the likelihood of an A or a B, but who’s to say it has never happened. Just this. The type A factor is not made in one step, but only in a sequence of steps. Type A results only if every step succeeds. So if one parent lacks a gene for some enzyme used in one the steps, but has all the biochemical apparatus for the remaining steps and the other parent has a gene that manufacturers the missing enzyme, then they can produce a type A child. I had actually conjectures that something of this sort could happen and the geneticist confirmed that it could and occasionally did. Bus mistyping still seems likelier to me. ---
**Author:** ![Rhaegar](https://avatars.discourse-cdn.com/v4/letter/r/51bf81/32.png) [@Rhaegar](https://boards.straightdope.com/u/Rhaegar)\ **Post date:** [May 30, 2012, 10:40pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/15 "2012-05-30T22:40:30Z")
O blood type is recessive, meaning that both your parents should be OO. Ergo, all their children should also be O blood type as well. Of course blood types are frequently misremembered by people, so I would confirm that all the blood samples are rechecked before drawing any conclusions. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [May 30, 2012, 10:59pm UTC](https://boards.straightdope.com/t/ab-blood-type/623557/16 "2012-05-30T22:59:54Z")
> [@Hari\_Seldon](#): > > IThe type A factor is not made in one step, but only in a sequence of steps. Type A results only if every step succeeds. So if one parent lacks a gene for some enzyme used in one the steps, but has all the biochemical apparatus for the remaining steps and the other parent has a gene that manufacturers the missing enzyme, then they can produce a type A child. > > I had actually conjectures that something of this sort could happen and the geneticist confirmed that it could and occasionally did. > > Bus mistyping still seems likelier to me. You are essentially describing the [Bombay Blood Group](http://en.wikipedia.org/wiki/Bombay_blood) phenomemon (as noted by Mr. **Smeghead** above). As an aside, I strongly suspect that a typo is more common, much more, than the Bombay Blood Group (1:250000). ---
**Author:** ![zameria](https://avatars.discourse-cdn.com/v4/letter/z/96bed5/32.png) [@zameria](https://boards.straightdope.com/u/zameria)\ **Post date:** [May 31, 2012, 3:04am UTC](https://boards.straightdope.com/t/ab-blood-type/623557/17 "2012-05-31T03:04:38Z")
I have the Death certificate of my Father, it states his is O+ as well as the donor information for him stating he was O+, my Mother is alive and knows for a fact she is O- due to her numerous surgeries. I am O+ and my brother is a factual AB+…no typos, plus my father was in the marines and it states it on his dog tags…So looks like I need to look deeper into this to find the “how’s” and “why’s”. Wish there was a way I could find a definite way to know… ---
**Author:** ![mnemosyne](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)\ **Post date:** [May 31, 2012, 3:39am UTC](https://boards.straightdope.com/t/ab-blood-type/623557/18 "2012-05-31T03:39:52Z")
> [@KarlGauss](#): > > How so? I assume you mean simply by using Rh- blood (which is quite different than “removing” the antigen is question). You make me doubt myself. I was - until this post - rather thoroughly convinced that the blood could be filtered or centrifuged (I don’t know the technique) to selectively remove the Rh+ while leaving behind usable blood products for donation to Rh- patients. Is that not correct? I swear I’ve been told this in First Aid and in my biochemistry classes (I have a BSc in the subject) but if I’m wrong I really would like to know in order to correct my misconceptions! I’m sure you deal with this on a more practical basis (rather than my outdated, merely theoretical basis) so I’ll defer to you here! ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [May 31, 2012, 9:46am UTC](https://boards.straightdope.com/t/ab-blood-type/623557/19 "2012-05-31T09:46:45Z")
And, now you’ve made me doubt _my_self . . . let’s check . . . No, it’s as I said: [Transfusion of Rh negative blood is what you should give to Rh negative recipients](http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0CMIEEBYwBg&url=http%3A%2F%2Fwww.health.gov.nl.ca%2Fhealth%2Fbloodservices%2Fprograms%2Fguidelines_for_blood_component_substitution_in_adults_ver2.pdf&ei=9jnHT9CRKcyJ6gGy7KGWDg&usg=AFQjCNHs2cfRGBSmzUkSSxl_kZHbZrvpLg&sig2=38ylSqdERcd95RKdJfS9zw). [Washing of red blood cells before they’re transfused is sometimes done](http://www.transfusionmedicine.ca/sites/transfusionmedicine/files/PDF/CGT-15%20revised%20Apr%202011.pdf) but only in order to remove various antigenic plasma proteins that may have been adsorbed onto the red cells. Rh antigens, being actually expressed on the RBC membranes, cannot be removed by washing free such plasma proteins. A classic use of blood washing is to remove IGA immunoglobulins before transfusing RBCs from an IGA positive donor into an [IGA negative recipient](http://en.wikipedia.org/wiki/IgA_deficiency). ---
**Author:** ![Antigen](https://avatars.discourse-cdn.com/v4/letter/a/848f3c/32.png) [@Antigen](https://boards.straightdope.com/u/Antigen)\ **Post date:** [May 31, 2012, 10:51am UTC](https://boards.straightdope.com/t/ab-blood-type/623557/20 "2012-05-31T10:51:35Z")
> [@mnemosyne](#): > > The Rhesus factor (the positive/negative when referencing blood groups) is rather easily removed from whole blood for donation, so it’s rarely an issue. That said, yes, O negative more worthy of the “universal donor” name than the positive. Nope nope nope. Rh negative folks can get Rh positive blood once, and sometimes more than once, in an emergency. That’s because the antibodies against the Rh (D) aren’t formed until the body’s been exposed to it, as opposed to the Anti-A and Anti-B that are naturally occurring in the body (depending on blood type). Trust me, if there was an easy way to strip antigens from blood, it would make the blood bank a much easier place to work, and we could stop hounding the rare blood types to donate more often. I need to get to work, but I’ll be back for more on this later. Antigen, MLS(ASCP) [Next page](https://boards.straightdope.com/t/ab-blood-type/623557.md?page=2)