Blood type group systems, 308 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
Jehovah's Witnesses and blood transfusions eating blood to prohibit the medical transfusion of human blood. Osamu Muramoto has argued that the refusal by Jehovah's Witnesses of "life-saving" blood treatment creates serious bio-medical ethical issues. He has criticized the "controlling intervention" of the Watch Tower Society by means of what he claims is information control and its policy of penalising members who accept blood transfusions or advocate freedom to choose blood-based treatment. He says the threat of being classified as a disassociated Witness and subsequently shunned by friends and relatives who are members coerces Jehovah's Witnesses to accept and obey the prohibition on blood transfusions. In