<P> A complete blood type would describe a full set of 30 substances on the surface of RBCs, and an individual's blood type is one of many possible combinations of blood - group antigens . Across the 35 blood groups, over 600 different blood - group antigens have been found. Almost always, an individual has the same blood group for life, but very rarely an individual's blood type changes through addition or suppression of an antigen in infection, malignancy, or autoimmune disease . Another more common cause in blood type change is a bone marrow transplant . Bone - marrow transplants are performed for many leukemias and lymphomas, among other diseases . If a person receives bone marrow from someone who is a different ABO type (e.g., a type A patient receives a type O bone marrow), the patient's blood type will eventually convert to the donor's type . </P> <P> Some blood types are associated with inheritance of other diseases; for example, the Kell antigen is sometimes associated with McLeod syndrome . Certain blood types may affect susceptibility to infections, an example being the resistance to specific malaria species seen in individuals lacking the Duffy antigen . The Duffy antigen, presumably as a result of natural selection, is less common in ethnic groups from areas with a high incidence of malaria . </P> <P> In human blood there are two antigens and antibodies . The two antigens are antigen A and antigen B . The two antibodies are antibody A and antibody B . The antigens are present on the red blood cells and the antibodies in the serum . Regarding the antigen property of the blood all human beings can be classified into 4 groups, those with antigen A (group A), those with antigen B (group B), those with both antigen A and B (group AB) and those with neither antigen (group O). The antibodies present together with the antigens are found as follows: </P> <P> 1 . Antigen A with antibody B 2 . Antigen B with antibody A 3 . Antigen AB has no antibodies 4 . Antigen nil (group O) with antibody A and B . </P>

Ab neg can receive what type of blood