Irritierende Ergebnisse einer DNA-Analyse aus Mischspuren. Wie viele Personen haben die Spur verursacht?

One of the basic principles in molecular genetic investigations of traces to obtain DNA profiles and assigning persons to traces is the fact that the genetic information in every cell of a person's body is identical;however, persons who have had an allogeneic stem cell or bone marrow transplantation are special. Every newly generated cell from the bone marrow now carries the genotype of the donor and not of the recipient, although all other cells show the recipient's genotype. This now results in two different DNA profiles for just one person depending on the cell material available for investigation. In one particular case of sexual assault a swab from the hand of a person who had received a stem cell transplantation was examined. The results showed a mixture of the DNA profiles of the donor and of the recipient. A possible explanation could be new Langerhans cells originating from monocytes derived from the donor's bone marrow.