> although egalitarians suggest that only a racist would consider race when it comes to reproduction and mate choice, this study observed a general, innate tendency to prefer one's own race especially when most likely to be impregnated. race is a social construct? the immune system: how important is race? > "if nick glasgow were white, he would have a nearly 90 percent chance of finding a matching bone marrow donor who could cure his leukemia." the reason that mixed-heritage patients are so hard to match can be found in the immune system. different races have developed certain proteins, or markers, that are part of the body's natural defenses. these markers help the immune system determine which cells are foreign and should be rejected. are cells racist? a match between two people who share more genetically in common significantly reduces the risk of the donor and recipient cells attacking each other. (read: cells from people of two different races will attack and fight each other as though they are a virus) the more people of different backgrounds who produce offspring = the more types that are harder to match. multiracial patients have uncommon profiles and since there can be many possible racial and ethnic combinations in multiracial societies, finding a match can still be extremely difficult.  
Canada