Blood Transfusions

I always thought that if a person needed a blood transfusion (or bone marrow or an organ transplant for that matter), the important thing was that the people had to have the same blood type.

But for a long time now I’ve seen that only people of the same race or even the same ethnicity can provide the needed transfusion or transplanted organs to one another.

What was the reason for this change?

For organ transplants, it’s not just the same blood type, it’s the same tissue type, which I believe has four different factors instead of just one.

Other than that, I don’t really know.

For organ transplants, the MHC type (major histocompatibility complex; also called HLA, human leukocyte antigen, in humans) is critical. The MHC region is the most polymorphic region of the genome. There are many alleles at many loci, giving a huge number of possible combinations. The closer the match, the better. For blood transfusions this doesn’t matter.

More on tissue typing.

Even blood typing isn’t fool proof. I was kept an extra day in the hospital because a transfusion caused me to break out in hives. Never found out why.

Just an anecdote, FWIW.

Just to add a tiny bit of information, it isn’t “the important thing” to have the SAME blood type, though it’s usually safest.

In most of the major blood typing systems, such as the ABO and rhesus factor, there is some kind of lattice system where anyone above can give to anyone below, or something like that. It’s only when the blood being transfuses has an antigen that the recipient has antibodies against that there’s a reaction, or something of that sort, and not the other way around. (Unless it’s the other way around and not that way. :wink: But not both.)

That’s why there’s a universal donor blood type and a universal recipient in the ABO system.

On the other hand, there are a lot of other blood type factors that are less likely to cause a bad reaction, but as long as they can hospitals don’t want to take chances.

Can you give a source for this? I used to work in a Blood Bank, setting up transfusions. There are minor differences in blood types and compatibility, but racial or ethnic matching was never considered.


I visited a blood clinic in Long Beach,Ca.
This was a disgusting reality. The clientele selling their blood were the homeless,
drug-using street people type.Filthy,smelly most of all,unhealthy.When not selling
aluminum cans,they are selling their blood…

Don’t trust or Beleive Me? Go visit your local blood clinic in any major city and you’ll get a dose of reality…

Well, first of all, the FDA has strict regulations about how blood and blood products are collected, handled, processed and prepared for transfusion. Among other tests, all transfusion products are tested for HIV, Hepatitis diseases, several sexually transmitted diseases and now West Nile Virus. Donors are assigned a unique identifier that appears on every product derived from their donation that is traceable all the way to the recipient. Before anyone is allowed to donate blood for transfusion, they must pass a lengthy questionnaire asking very detailed questions about their sexual, disease and drug use history, as well as travel, tattoo, surgery and cancer history. A “Yes” answer to most of those questions will get you a firm “Thank you, the door is to your left.”

Plasma from donation sites that pay for donations is used for creating medical clinical machine quality control material, and even then it is screened for at least HIV and hepatitis. It may also be used to create plasma-derived products used in industrial applications. Plasma from pay sites does not meet minimum FDA safety requirements for transfuable products, and is not used for any type of transfusion.


My main source are the reports I’ve seen (and continue to see) on television, which contain pleas for people of colour to become blood donors or organ donors for people of their own particular racial group. (For example, Asian people have been called on to make blood or organ donations to other Asian people.)
I guess I was just a little surprised about this because I always thought that under the skin, race didn’t really matter, and as long as blood and tissue were compatible we could give of ourselves freely to help a fellow human being.

For tissue matches, it is so helpful to have more matches in the minor compatability factors. Chance of rejection goes way down when this occurs. That’s why family donors are preferred over unknown donors, even if the major compatability factor matches are equal.

So if one can’t get a family member donor, the next best thing is to draw on the same general genetic pool, whether it’s a group of descendants from a particular northern european region, or a region derived from western equatorial africa, or from southeastern asia.

Race (a spurious concept anyway) doesn’t matter. But ethnicity does figure into it. And some ethnic groups don’t donate tissue as often as would be desired given the number of members of that ethnic group who need tissue donors. So the more diversity we have in the tissue banks, the more people we can serve.


Ray Caruth’s daughter was of black/eastern European Jew ancestry. When she got diagnosed with a rare form of leukemia, the family scrambled to find blood donors with similar parentage. Unfortunately, I believe the quest was unsuccessful and she died.

When I donated blood in college, I was signed up for the African American Bone Marrow registry. For whatever reason, black people don’t sign up in high numbers, thereby putting black patients in need of a bone marrow up a creek.

On the news last week, there was a story about an Indian-American woman who was in dire need of a bone marrow transplant. Her friends were going to Indian communities to sign people up.

Race does not exist in a biological sense, but populations do. We don’t mate randomly, and we’re more likely to mate with someone who looks like us (and share our culture, etc.) Sometimes it happens that race is a good proxy for population.

Urticaria is the most common adverse reaction to a blood transfusion but so far as we know it has nothing to do with blood types. From what I’ve read it seems that researchers suspect the white blood cells in the donated unit to be responsible for that reaction, as well as some other not so harmless ones. A lot of blood centers, including the one here, have moved to producing only leukoreduced units-the white cells are filtered out after the unit is collected.
Premedication with benadryl usually prevents any more hives from further transfusions.

I’ll remember that if it comes up again. (crosses fingers)

There’s several different reactions that one can get from having a blood transfusion. I know the most usual for me is hives (I can tell this one because I start itching all over then I start to see the hives along the insides of my arms). Other reactions can include nausea, pain in the back (I’m not sure how this one was caused; only happened to me twice), or chills.

When I get a reaction the response is to put some benadryl in me. Now on doctor’s orders they always premedicate with benadryl and tylenol.

Ok, now I see what the question is about.

The cells in your body, including red cells, are studded with proteins like a porcupine. During fetal development, your immune system “learns” the proteins your cells will have. Anything not detected by your immune system will be considered foreign, and your immune system will attack it. This is the basis of organ/tissue rejection, as well as the basis for some allergic reactions to transfusions. These proteins are somewhat race- or ethnically-specific, so it is important to match the race and ethnicity of the donor and recipient whenever possible to ensure the most successful transplant possible.

Off hand, I know of HbS, or hemoglobin S; One copy of the HbS gene creates one unit of hemoglobin S, which protects against malaria-bearing mosquitos. Two copies of the HbS gene creates two units which in turn causes sickle-cell anemia. HbS is seen most frequently in African populations who live where malaria is prevalent. Another example are the Duffy A and Duffy B proteins on red cells. People of African origin do not have these proteins present, and that protects them from Malaria the same way HbS does. Most of the rest of the world has both Duffy proteins which doesn’t protect them. Africans who receive blood in non-African countries stand a good chance of developing anti-Duffy antibodies, which can create problems for later transfusions or organ transplants. There are many other such proteins present on organ cells that I don’t know about, but the end effect is the same if they are not carefully matched to the recipient.