ABO blood group system roles in cell membrane integrity, cell adhesion, membrane transportation of molecules, and acting as receptors for extracellular ligands, and enzymes. ABO antigens are found having similar roles on epithelial cells as well as red blood cells. The ABO antigen is also expressed on the von Willebrand factor (vWF) glycoprotein, which participates in hemostasis (control of bleeding). In fact, having type O blood predisposes to bleeding, as 30% of the total genetic variation observed in plasma vWF is explained by the effect of the ABO blood group, and individuals with group O blood normally have significantly lower plasma levels of vWF
Blood type personality theory Dr LAURENT: "4groupes sanguins, 4 personnalités" Marco Pietteur ed. 2007/2014. Belgium. (In French) Blood type personality theory A pseudoscientific belief exists in some East Asian countries, that a person's ABO blood type is predictive of a person's personality, temperament, and compatibility with others. This superstition is similar to how astrological signs are perceived as influencing factors in a person's life in other countries. One of the reasons Japan developed the blood type personality indicator theory was in reaction against ethnic stereotypes coming from Europe. The popular belief originates with publications by Masahiko Nomi in the 1970s. The scientific community generally