How would a blood transfusion affect a DNA test?

[Rosinish]

Could someone please explain whether a large blood transfusion of over 12 pints would affect a true DNA match?

Apologies if this has been covered before but I couldn't find a thread on it.

Annie

Add...Since reading some replies can I ask for any replies in laymen terms as much as is possible as many words on the subject are alien to me 

[Skoosh]

Be interesting to see the answer Annie. I fancy that blood would be replaced naturally by new stuff?

Skoosh.

[Ayashi]

I can't imagine that it would, in terms of Ancestral DNA tests. I haven't taken one myself but aren't these tests usually taken via saliva? When the police do tests I think they usually swab the inside of the cheeks.

If someone did test blood for whatever reason, such as in a crime scene, then a recent transfusion would complicate matters. If you had the transfusion say ten years ago it would have been replaced by your own natural blood by now.

[Wred]

intresting article here https://www.quora.com/What-happens-to-a-donors-DNA-in-a-blood-transfusion

Answer seems to be generally no but maybe for short time.

Have heard that constant scratching of skin of ears ( from exzema) can change dna of area. Wonder if that means one part of body is therefore alien to the rest?

[Erato]

Red blood cells have a lifespan of about 120 days but they don't have a nucleus so they would only be carrying mitochondrial DNA.  White blood cells have a shorter lifespan - less than a month.

[Ayashi]

I suppose an interesting but unrelated to the topic variant to add into the mix would be chimerism. I wonder if it is possible for twins with different fathers to create a chimera or if the combination would abort itself. I also wonder how many of us doing DNA tests actually provide a DNA sample to these places that is different to the DNA we ourselves pass on. At least we would still be related to the same people though!

[Gadget]

Some info that may help here, Annie:

http://www.rootschat.com/forum/index.php?topic=787725.msg6431543#msg6431543

Gadget


Added - from second ref:

Chimerism does indeed make DNA testing more complicated. In the case of bone marrow, a DNA test from a blood sample would match the donor while a test from hair or saliva would match the recipient. The recipient would also have the blood type of the donor if they did not already match.

[pinefamily]

I don't think a blood transfusion would, but I remember reading somewhere that a bone marrow donation can.

[Rosinish]

Thanks to all who have replied with thoughts/knowledge/links!

I was aked the question myself which I thought would be very interesting to know, not only for myself but for others too who may have had a transfusion & have had thoughts about a DNA test & what the outcome may be (if any) through a transfusion.

All interesting to myself &/or (anyone else with no knowledge) to know their DNA test will have no effect from a transfusion!

Annie