A Human Chimera Shows Why DNA Evidence Is Questionable

December 9, 2019

(Quartz) – Chris Long, an American who had a bone marrow transplant, discovered this firsthand when his genetic tests came back showing not only his own DNA, but also that of his German donor—in his blood, cheeks, and even semen. He learned this because he happens to work in the Washoe County sheriff’s office in Nevada. Long’s colleagues in the forensics unit were curious about just what the procedure would do to his DNA. He submitted to their requests to be a human guinea pig.