The implications for criminal forensic work are fascinating.

A Nevada man discovered his DNA had changed after a bone marrow transplant and had been replaced, in part, by that of his German donor.

Chris Long, from Reno, found that not only had his blood swapped, but his semen was also changed, following his treatment for leukemia.

Long, who works at Washoe County Sheriff’s Department, told The New York Times: ‘I thought that it was pretty incredible that I can disappear and someone else can appear.’

Now his police colleagues are looking into how such changes could affect criminal cases and forensic work.

[…]

Long found that all the DNA in his blood had changed three months after his operation. It was four years later he discovered that parts of his lips and cheeks also contained the DNA of his donor.

The change has made him a chimera, which means he has two sets of DNA.

Only his chest and head hair were not affected, according to all the samples taken.