Human blood already comes in a bewildering variety of types, but researchers have now identified a new one so rare that only ...

Von Willebrand disease (VWD) is a bleeding disorder in which the blood does not clot as it should. Usually, people have VWD due to their genes, which may come from a male or female parent. Blood ...

That seemingly arbitrary letter you rarely think about could be silently influencing your health in surprising ways. Your blood type, determined before birth and unchanged throughout life, extends far ...