A pregnant woman's blood sample taken in 1972 was mysteriously missing a surface molecule found on all other known red blood ...

After half a century of puzzling over a handful of unexplained transfusion reactions, researchers have finally traced the problem to something hiding in plain sight: an entirely new blood group system ...

For half a century, a tiny quirk on the surface of red blood cells has puzzled doctors and put a small group of patients at risk during transfusions. That mystery has now been resolved with the ...