Blood typing: MedlinePlus Medical Encyclopedia

blood group  The meaning of BLOOD GROUP is one of the classes into which individuals or their blood can be separated on the There are 4 main blood groups

The newly discovered variations within the blood group system, Er4 and Er5, are extremely rare, but they have been implicated in cases of Like eye color, blood type is passed genetically from your parents Your blood type is determined by your ABO type and a negative or

Individuals with type A blood—without any prior exposure to incompatible blood—have preformed antibodies to the B antigen circulating in their blood plasma  ABO blood group system, classification of human blood as determined by the presence or absence of A and B antigens on red blood cells