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No, at one point a German physician suggested using zero, as it contains no antigens. But Karl Landsteiner, who proposed the eventual system that would come to be used around the world, suggested “O” for “ohne,” meaning “without”–as in, without antigens.
No, at one point a German physician suggested using zero, as it contains no antigens. But Karl Landsteiner, who proposed the eventual system that would come to be used around the world, suggested “O” for “ohne,” meaning “without”–as in, without antigens.