How to Test for RHD Antigens

CNN's John Defterios sits down with Dr. Michael Schulder to talk about testing for RHD and some of the new information that has been revealed in recent years. He starts off by talking about how simple it is to do a pre-transfusion test, but there are other options if you're not sure what your blood type is. And then he goes on to discuss his research into variant RHD antigens which could be used as part of an early warning system when someone gets sick.