MYSTERY WIRE — Chris Long is a chimera.
The term refers to an organism that has the DNA of two individuals. In Long’s case, a bone marrow transplant produced the condition. All of Long’s blood contains the DNA of the marrow’s donor, a German man.
A study publicized in a New York Times article, “When a DNA test says you’re a younger man, who lives 5,000 miles away,” surprised researchers when the donor’s DNA showed up beyond his bloodstream — in cheek swabs, in lip swabs, and even in his semen.
Long works in information technology for the Washoe County Sheriff’s Office in Reno. His case brings with it a number of interesting questions regarding forensic science and law enforcement:
- Does an individual with two sets of DNA change the validity of convictions based on DNA evidence?
- What is the extent of DNA’s “spread” within another individual’s body?
- When is the “chimera” effect temporary, and when is it permanent?
- Do bone marrow transplants carry the possibility of passing on someone else’s DNA to offspring?
The last question, regarding offspring, is addressed in a New York Times follow-up, in which readers’ questions are answered.
See also: Known circumstances that have produced human chimeras (Scientific American, 2016)