If you have had a blood transfusion recently how would it affect a DNA test?

Question

My ten year old son asked me this .

Answer 1

The short answer is "no," and the longer answer is "no way."

It seems blood is composed of four main elements: red blood cells, white blood cells, platelets, and plasma. And, indeed, white blood cells do contain DNA. However, most blood transfusions involve only red blood cells, which do not contain DNA. And even in a rare whole blood transfusion, no traces of foreign DNA from the white blood cells have been detected in a recipient's blood.

On the other hand, there is at least one situation in which a transplant can change your DNA. After a bone marrow transplant, the DNA in a blood sample may actually reflect the donor rather than the recipient. That's because in this case, blood stem cells are transferred. The recipient will produce blood that contains the donor's cellular elements but almost none of his or her own DNA. And yes, this would affect DNA blood evidence (though there are other ways to test for DNA.)

Then there's the even rarer case of blood being transferred due to the anti-social behavior of vampires. But that's a whole other ball of serum.

Answer 2

The short answer is "no," and the longer answer is "no way." We assembled our own little blog of blood to explain, drawing from a San Diego Union Tribune column, a posting on the MadSci Network, and several other sources.
It seems blood is composed of four main elements: red blood cells, white blood cells, platelets, and plasma. And, indeed, white blood cells do contain DNA. However, most blood transfusions involve only red blood cells, which do not contain DNA. And even in a rare whole blood transfusion, no traces of foreign DNA from the white blood cells have been detected in a recipient's blood.

On the other hand, there is at least one situation in which a transplant can change your DNA. After a bone marrow transplant, the DNA in a blood sample may actually reflect the donor rather than the recipient. That's because in this case, blood stem cells are transferred. The recipient will produce blood that contains the donor's cellular elements but almost none of his or her own DNA. And yes, this would affect DNA blood evidence (though there are other ways to test for DNA.)

Answer 3

If you did a blood DNA test you could detect all the DNA of all the donors that donated blood to you.

However it is cheaper and safer to use skin cells from your mouth, and the DNA of these would in no way be impacted by a transfusion.

Answer 4

DNA is tested by a swab of the inside cheek bone.

Answer 5

You probably need to ask a doctor.

Answer 6

i think it would be safer if u r take it from mouth than other part of body.

Answer 7

ASK A DOC

Answer 8

it wont affect anything

Answer 9

I don't think it does.