I want to do a story set in WWII and one of my climaxes is when a Jewish soldier gives blood to save a German soldier’s life (or vice versa). My question is this: do different races have different blood types? Like, do Jews have a blood type no one else has? I don’t want to do something medically incorrect just because I think my story is good.
There are eight different blood types and all ethnicities/races can have one of these blood types though some are more prevalent in a race than others. Here is an interesting link where the Oklahoma Blood Institute looked at what blood types certain races were and their break down.
I think the harder part of your question is would these two soldiers, by chance, have the same blood type where it wouldn’t cause a life threatening reaction in the soldier receiving blood. I was able to Google this question and found this link. As you can see, the best odds are if both soldiers are O-positive and yet that random chance that both are the same blood type is only 38%. The next highest is if both are A-positive at 34%. The other blood types fall precipitously after that. Of course, if the soldier giving the blood is O-negative (this is the universal donor) then there should be no reaction regardless of what blood type the receiving soldier is. On the reverse side, the universal recipient (someone who can get anyone’s blood) is AB-positive.
It would actually increase conflict in your story if the soldier receiving blood DID have a transfusion reaction. This type of reaction would be called a hemolytic transfusion reaction. This article reviews some of the varied responses a patient can have. Of course, you’d have to consider the time frame of your piece and what treatment would have been available then.
Hope this helps and good luck with the story!