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Q: DNA Research ( Answered 5 out of 5 stars,   1 Comment )
Subject: DNA Research
Category: Health > Conditions and Diseases
Asked by: jaydub1983-ga
List Price: $10.00
Posted: 02 Dec 2003 16:50 PST
Expires: 01 Jan 2004 16:50 PST
Question ID: 282837
If a person gets a blood transfusion does their DNA change?
Subject: Re: DNA Research
Answered By: pinkfreud-ga on 02 Dec 2003 17:38 PST
Rated:5 out of 5 stars
Receiving a blood transfusion will not change a person's DNA in a
long-term way. The most that can happen is that testing (if conducted
shortly after the transfusion) might reveal the presence of both the
patient's own DNA and foreign DNA from the blood donor. Unless the
transfusion involves white blood cells or platelets, there may be no
detectable change at all.


"With all the forensic shows at the moment, I would like to know.....
if you can get DNA from blood, and you can get a full/partial blood
tranfusion, does this effect/change your DNA?...

Red blood cells have no nucleus, and therefore carry no DNA, but red
blood cells only make up a small part of the fluid we know as blood.
There are also white blood cells present in many forms. These guys are
part of our immune system, and they do have DNA. It is this DNA that
scientists can extract from most blood samples and match back quite
specifically to its owner!

If you were to have a blood transfusion, say after being in an
accident and needing surgery, you would be given someone else's blood,
but you will always have some of your own white blood cells floating
around as well (actually the number of your own will dramatically
increase due to the trauma), so if you were to subsequently commit a
crime and leave blood at the scene (within about a month) that blood
would give a result similar to one which has been mixed or
contaminated (and depending on how many different donors you received
the blood from, that could get quite confusing!).

If you were suffering from a 'blood' cancer such as leukaemia, and had
a bone marrow transplant, where your marrow was completely irradiated
to kill it first, from that point forward (if you survived) you would
produce white blood cells that carried your donor's DNA."

Australian Broadcasting Corporation Science Forum


"If I have a blood transfusion, does that change my DNA?...

There have been many studies that have been done on whether or not
blood transfusions change a person's DNA. You can certainly identify
when a person has a fresh transfusion, but their own DNA profile does
not get removed. As the days post-transfusion go forward the
transfused blood profile does get removed from the blood, so there
really would not be an extreme concern about this. You might get a
confused answer to begin with. You would see the person's own profile
and the transfused profile originally, but that fades fairly quickly."

US Department of Justice: National Law Enforcement Summit on DNA Technology


"Q: If an offender has had a blood transfusion, will two DNA profiles
appear in any biological evidence he/she has left at a crime scene?

A: It is possible, but unlikely. It will partly depend on the type of
transfusion received. If a person has received only red blood cells
(which do not contain DNA), there will be no confusion. If the person
has received white blood cells or platelets (both of which contain
DNA), there could be a mixture of recipient DNA and donor DNA in the
sample. Upon analysis, both DNA profiles would be identified. They
will not 'mix' to create one, new profile.

Keep in mind that the human body will replace all transfused blood
cells within three or four weeks. If the transfusion was minor, the
recipient's original DNA profile would be clearly prominent. If the
transfusion was major, the recipient will probably be too ill to
commit a serious crime before their body has replaced most of the
donor cells."

National DNA Databank of Canada: Blood Transfusion/Bone Marrow Donations


"Would the DNA profile from someone who has been the recipient of a
whole blood transfusion reflect some (any?) characteristics of the
blood donor. If so, how long would these characteristics remain?...

No, a person who received a whole blood transfusion would not display
detectable amounts of the donor's DNA profile. Due to certain
limitations, whole blood transfusions are rare; most blood
transfusions today are done with what's called packed red blood cells,
a.k.a. erythrocytes, which perform the function of transporting oxygen
and carbon dioxide to and from the cells of the body. Erythrocytes
contain no DNA, however, having lost their nuclei during maturation...
White blood cells, a.k.a. leukocytes, contain nuclei and are the
agents that provide a DNA profile from blood. In whole blood
transfusions, the whole soup is transfused from one person to

In actual observation, the DNA profile of a blood donor has not been
detected in the peripheral blood of a recipient, regardless of how
much was transfused. In one study, a woman was transfused with 14
units of blood (four whole, ten packed red cells), while a man
received 13 units (four whole, nine packed red cells). In both cases,
neither individual had detectable levels of the foreign DNA profile,
despite being tested as late as the following day."
The Straight Dope: Does a blood donation mess up DNA evidence?


Google Web Search: "transfusion" + "change * dna"


I hope this information is useful. If anything is unclear, or if a
link doesn't work for you, please request clarification; I'll be glad
to offer further assistance before you rate my answer.

Best regards,
jaydub1983-ga rated this answer:5 out of 5 stars and gave an additional tip of: $10.00

Subject: Re: DNA Research
From: pinkfreud-ga on 15 Dec 2003 09:45 PST
Thank you very much for the five-star rating and the generous tip.


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