If I committed a crime the day after having a full blood transfusion and left some of my blood at the scene of the crime, would forensic scientists be able to detect my DNA in it? Or would their analysis result in confusion? I hasten to add that it is unlikely that I would feel well enough to commit any crime after a transfusion, and I also have no intention of trying this out.
Blood has three cellular components: red blood cells, white blood cells and platelets. Only the white cells are complete cells with nuclei and DNA. These three elements are typically separated when donated blood is processed. The blood used for transfusion only contains red cells, which lost their mitochondrial and nuclear DNA during development.
Even a complete exchange transfusion would not result in the donor's DNA being left at a crime scene. Large numbers of white cells ...
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