What my colleagues have done is take the parts of the h.i.v. virus that are good at getting in cells get rid of the parts that kill the cells and replace that where molecules that can target the cells to fight leukemia so use the good parts without the bad part. >>shepard: how do you get the bad part out? >>guest: the scientist whose do this have biology techniques with mol cues and enzymes that can chop out the bad parts, splice the good parts together, and you can put in new information so the h.i.v. virus rather than making proteins to make the cell sick make proteins to make the cells kill...