As I think back during my slave days as an employee and had to do medical check ups. First thing they did was drawn blood. Wonder what they did with all the blood they drew from people every day. Interestingly enough I've always asked the nurse what is my blood type and she would never tell me. To this day I have no idea. Wasn't interested in genealogy, didn't care who my people were, so never did the 123 and Me, or the Mormon ancestry tests, etc...