Here is a fascinating article about a man who temporarily ended up with three different sets of DNA in his body after an experimental cancer treatment.
It is actually a most enlightening article on what is possible nowadays in the area of DNA manipulation. Let us for a moment imagine a goon hired to cause harm to others – how much easier would it be, knowing that a reliable DNA trace cannot be left behind?
Nevertheless, this article also provides insight into the reality of DNA changes taking place in an alive human body.
Article published by Portland Press Herald at the following address:
http://pressherald.mainetoday.com/story.php?id=138639&ac=PHnws
It is actually a most enlightening article on what is possible nowadays in the area of DNA manipulation. Let us for a moment imagine a goon hired to cause harm to others – how much easier would it be, knowing that a reliable DNA trace cannot be left behind?
Nevertheless, this article also provides insight into the reality of DNA changes taking place in an alive human body.
Article published by Portland Press Herald at the following address:
http://pressherald.mainetoday.com/story.php?id=138639&ac=PHnws
Josie Huang said:Experimental cancer treatment includes a genetic bonus 'Wild thing' meshes with experimental DNA treatment
Not long ago, Greg Graves would have laughed at the thought of walking around with multiple sets of DNA. The first time he even heard of the possibility was on the TV show "CSI: Crime Scene Investigation."
"There was this guy who had two different types of DNA because he absorbed his own twin," Graves said. "They got a DNA sample from the crime scene that was different from when they tested him."
Little did the Cape Elizabeth man know that for a time he would be carrying three sets of DNA.
A year into his diagnosis with an advanced stage of non- Hodgkin's lymphoma – a blood cancer that killed his father and two paternal uncles – conventional treatment did not seem to be working. So last summer, at age 48, he went to the Dana-Farber Cancer Institute in Boston for an experimental transplant of stem cells intended to regenerate his blood.
Traditionally, the donor would have been another adult. But for this procedure, doctors used stem cells from the discarded umbilical cord blood of two anonymous babies – a boy and a girl.
Cells from both babies co-existed in his body for a while, then the boy's took root in the bone marrow and started producing healthy blood cells. Now, the genetic makeup of Graves' blood has gone from O-positive to the boy's O-negative type.
"If you were to do a DNA test of my blood and one from my skin, they'd be different," Graves said. "It's a pretty wild thing."
NO MATCH FROM BONE MARROW
The procedure performed on Graves is part of a worldwide effort to make stem cell transplants available to nearly every patient with a blood cancer, such as lymphoma and leukemia, or disorders of the bone marrow.
Currently, most of these patients get transplants from donors of bone marrow, a rich source of stem cells, also known as the body's "master cells" because they can turn into other tissues and organs.
About a third of patients are matched with a sibling – the ideal scenario – and another third can find a match among the more than 10 million people listed in bone marrow registries, said Dr. Claudio Brunstein of the University of Minnesota, where double- cord blood transplants originated.
Unfortunately, some of the matches made through bone marrow registries turn out to be worthless, because "you have a lot of people who move or no longer want to be donors," Brunstein said.
That leaves about 40 percent of patients without a match, Brunstein said. Graves was one.
For patients like him, the medical team at the University of Minnesota in 2000 decided to transplant stem cells from cord blood. Of the different types of stem cells, they are the youngest and most malleable, except for controversial embryonic stem cells, which are not used for medical treatments.
By that time, cord blood transplants had been widely performed in children, but a single unit would not provide enough material for an adult over 100 pounds. So the university team used blood from two babies' umbilical cords.
A CLOSE MATCH IS GOOD ENOUGH
Cord-blood stem cells are even less differentiated than an adult donor's, and matching is not as precise a science. That means all but 5 percent of patients "with the most unusual genetics" could find close enough matches, Brunstein said.
Graves' doctors at Dana-Farber picked cord-blood units based as much on the size of the batch as genetic appropriateness, and came up with a male O-negative donor and a female A- positive donor.
To set the stage for the transplant, doctors tried to wipe out Graves' malignant blood cells with chemotherapy. Then, on July 21, 2006, Graves received an injection of the babies' stem cells, and started a regimen of anti-rejection pills.
In most patients, the two sets of cells co-exist for several months. But a test of Graves' blood a month later showed that the baby girl's cells had vanished.
"We presumed it was just rejected," said Dr. Joseph Antin, Graves' doctor and the chief...
of transplantation at Dana-Farber. "We don't know if Greg rejected it or if the boy rejected the girl. We can't tell you any more precisely, other than it went away."
Graves said he is just glad his body "clicked" with the boy's cells. A year after the procedure, he is cancer-free and working part- time from home at his job as a principal with Milliman, an actuarial and consulting firm.
Graves is one of only several hundred people worldwide to have received the double-cord transplant. Dana-Farber is a leading provider of the transplant, having performed about 80 in New England since 2003, trailing only the University of Minnesota.
To promote cord-blood transplants, Dana-Farber is working on starting a cord-blood bank with the obstetrics department of Brigham and Women's Hospital.
Of the Dana-Farber cases, about 70 percent of the patients have survived their prognosis, and some of them are considered cured, Antin said.
Graves never received an official prognosis, but Antin said without the transplant, "most likely his disease would have progressed or devolved to a point where he's no longer treatable."
Now 50, Graves said he has thought about one day meeting the boy, whose sample came from North Carolina, and who should be 6 now. But Antin said that unlike adult donors, cord-blood donors cannot be identified, and may never know about their life-saving contribution.
"There's a boy out playing during recess and (he) has no clue that this is going on," Antin said.