Studies have shown that donor DNA in blood transfusion recipients persists for a number of days, sometimes longer, but its presence is unlikely to alter genetic tests significantly. Red blood cells, the primary component in transfusions, have no nucleus and no DNA. Transfused blood does, however, host a significant amount of DNA-containing white blood cells, or leukocytes—around a billion cells per unit (roughly one pint) of blood. Even blood components that have been filtered to remove donor white cells can have millions of leukocytes per unit.
Investigators have detected donor DNA after transfusion with a process called polymerase chain reaction (PCR) that amplifies minuscule amounts of genetic material for detection and identification of specific genes. Studies using PCR to amplify male genes in female recipients of transfusions from male donors have demonstrated that donor DNA endures in recipients for up to seven days. And a study of female trauma patients receiving large transfusions showed the presence of donor leukocytes for up to a year and a half.
All these results, however, were found using very sensitive techniques whereby donor DNA was selectively amplified over the more plentiful recipient DNA. In studies where genes common to both donors and recipients were amplified, the results reflected the dominance of the transfusion recipient’s own DNA, showing the donor’s DNA to be a relatively inconsequential interloper.
Note: This question was submitted by W. McFarland, Winter Springs, Fla. and printed in the February 2009 issue of Scientific American
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Add CommentI recently saw a tv show in which a corpse was misidentified because of dna in donor tissue. It made a good story line, even though it may be highly unlikely in reality.
Reply | Report Abuse | Link to thisWhat about a crime scene where the assailant received blood at some point prior to the act and left blood evidence. Could the donor be falsely identified as the perpetrator?
Reply | Report Abuse | Link to thisSounds like a plot for Law and Order, if not already.
Hmm....some interesting scenarios come to mind.
Reply | Report Abuse | Link to thisDoesn't answer the question - what happens to the donor DNA?
Reply | Report Abuse | Link to thisI would guess the same thing that happens to our own DNA as our bodies replace cells over time. It gets broken down, jettisoned or sloughed off in some way, to be replaced by the continual process of renewal. This is just a total layman's opinion, though.
Reply | Report Abuse | Link to thisIf blood transfusions contain white blood cells, could this lead to an autoimmune disease? Conversely, could it provide immunity to specific pathogens through these immune cells? That would be rather interesting indeed.
Reply | Report Abuse | Link to thisI wander if we donate blood and have DNA to have a healthy heart, would this good DNA trigger the repair of the heart in those who receive the blood with the good DNA, but their heart is sick??
Reply | Report Abuse | Link to thisAlso I read in: God's Medicine Is Best (herbs, vitamins and minerals) by Linda Wise, that BONEMEAL contains both phosphorus and calcium, and it can help with getting teeth in shape, like if one has cavities? I think this teeth thing is a genetic thing too, everybody in my family has bad teeth, so can it be altered?
The life span of white blood cells is short, less than three weeks. They are "processed", disassembled. The DNA is broken down into its component parts and either metabolized or reassembled into host DNA or RNA.
Reply | Report Abuse | Link to thisI just read the ineresting question. It relates to what happens in our bodies to the DNA ingested from food? We looked at that (Forsman et al, "Uptake of amplifiable fragments of retrotransposon DNA from the human alimentary tract", Mol Genet Genomics. 270:362-8 (2003). Around 3-4 hours after eating, a very small amount of food DNA was detectable for a few hours. Presumably this DNA is degraded and disappears. Jonas Blomberg MD PhD
Reply | Report Abuse | Link to thisI bleed to death on the operating table when I was a child. The hospital used a staff nurse and directly connected her to me to save my life in a blood transfusion. I have had unusual health problems in my life since then. I had another blood transfusion later in life at age 22 while in critical care. Can the use of other people's blood affect my health? I became pregnant 3 months later and my child has also had unusual health problems.
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