The total amount of blood drawn is approximately 5 tablespoons (75 ml). The blood sample will be processed to isolate "genetic material" (mainly DNA, RNA and protein). This genetic material will be used to try to identify the "genetic factors" or genes that a person inherits that make him or her more likely to develop asthma. The blood is used to test for allergies to weeds, trees, insects and molds (RAST) and a complete blood count.