Man’s DNA changes after bone marrow transplant

DNA. (PHOTO: Getty/Gallo Images)
DNA. (PHOTO: Getty/Gallo Images)

A man with Leukemia found that his donor’s DNA travelled to unexpected parts of his body. Now police in his home state of Nevada in the US are looking into how it could affect criminal cases and forensic work in the future.

Chris Long, an IT worker in the Washoe County Sheriff’s Department in Reno, Nevada, discovered that all the DNA in his semen belongs to a German man he’s never met. He received a bone marrow transplant from the European stranger four years ago.

Chris needed a transplant to treat his acute myeloid leukaemia, a type of cancer that prevents the body from producing blood normally, according to a New York Times report.

As a result of the procedure the healthy blood-forming cells from the donor replaced Chris’ unhealthy cells thus it makes sense for his blood to contain his donor’s DNA. It’s considered normal after a bone marrow transplant.

But Chris’ colleague Renee Romero, who run the office’s forensics lab, had a feeling that the transplant might affect the DNA elsewhere in his body, so she encouraged him to have samples of his DNA collected before the procedure to monitor any changes.

He agreed and since his procedure, his colleagues have collected numerous samples of his DNA from various parts of his body and had it tested. In certain places, such as his lips, cheeks, and tongue, the swabs revealed they contain DNA from both Chris and the donor, while samples that were tested of his chest and head hair, only shows Chris’ DNA.

The most interesting discovery was made when it was found samples of Chris’ semen only contain the DNA of his donor.

“I thought that it was pretty incredible that I can disappear and someone else can appear,” Chris told the NYT.

Darby Stienmetz, a criminalist at the Washoe County Sheriff’s Office, said: “We were kind of shocked that Chris was no longer present [in his semen] at all.”

The changes to his genetic makeup have made him a chimera – someone who has two sets of DNA. The word takes its name from a fire-breathing creature in Greek mythology composed of a lion’s head, a goat’s body and a snake’s tail.

But despite the significant changes to Chris’ genetic makeup, dr. Andrew Rezvani, the medical director of the in-patient Blood & Marrow Transplant Unit at Stanford University Medical Centre, insists that it shouldn’t affect a person's personality.

“Their brain and their personality should remain the same.”

But it’s been reported that such instances have swayed criminal cases, reports Mail Online.

After a DNA profile matched a suspect already in prison, investigators in a criminal case in Alaska in 2004 found he’d actually received a bone marrow transplant from his brother who was eventually convicted.

In 2006 a woman named Lydia Fairchild of Washington state, discovered that she wasn’t the mother of her children when she underwent testing as a requirement for applying for government aid following a split from the children’s father.

The children were nearly removed from her custody before extensive testing revealed that she was a chimera – she had the DNA of her own twin.

The bone marrow transplant experts the New York Times consulted also weighed in on an inevitable question: What happens if Chris fathers a child? Would he pass on the genes of his German donor or his own to future offspring?

“There shouldn’t be any way for someone to father someone else’s child,” said dr. Rezvani, adding that the question will likely remain unanswered because Chris had a vasectomy after his second child was born.

Dr. Rezvani further explained that both he and Dr. Mehrdad Abedi, a doctor at the University of California, believe Chris’ vasectomy could’ve played a role in his semen now containing his donor’s DNA, although this is something the forensic scientists plan to investigate further.

For his part, Chris says he hopes to meet his donor during an upcoming trip to Germany to thank him in person for saving his life.

Sources: New York Times, Abc News, Daily Mail

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