Howdy nonprofitstuff-ga,
There is no absorption of genetic code because in simple blood tranfusions only
red blood cells and plasma is transfused and neither have a nucleus, so no
individual genetic material.
This MadSci Network posting speaks to this.
http://www.madsci.org/posts/archives/feb2000/950993606.Bc.r.html
"But as far as blood transfusions confering the genetic identity of the donor
to the recipient, it is not possible. Blood has three components, reb blood
cells, white blood cells, and the fluid they are in called plasma. Simple blood
transfusions deliver only red blood cells and plasma. The only job of a red
blood cell is to delivery oxygen to all the tissues of the body. Transfusions
are given to replace lost blood and plasma during surgery or some trauma so
that the body can still deliver enough oxygen to the tissues. What is important
about this is that red blood cells contain no nucleus, and therefore no
individual genetic material."
Even in the case of a whole blood transfusion, there is still no transfer of
genetic material. The Argonne National Laboratory, Division of Educational
Programs website talks about this.
http://www.newton.dep.anl.gov/askasci/mole00/mole00663.htm
"No, there is no reasonable chance that DNA from blood transfusions or marrow
donations will mix with host DNA. Cells don't readily exchange their DNA,
except in the case of sexual reproduction. In order for such a mixture of
DNA to occur, you have to achieve a fusion of cell nuclei in such a way that
the nucleus and its cell remain intact and alive. That's a fairly difficult
trick, and it requires a lot of very specialized cellular apparatus and
behavior to pull it off. Somatic cells (those not involved in reproduction)
don't ever go around fusing their nuclei; it's just not a part of their
behavior."
There is some rejection that happens with blood transfusions, as pointed out by
this other MadSci Network posting.
http://www.madsci.org/posts/archives/may98/892767553.Im.r.html
"There is a group of molecules called Histocompatibility molecules or antigens.
These proteins are encoded by a group of genes called Major Histocompatibility
Complex or MHC genes, and they are present in the surface of the majority of
our cells.
...
Most of the immune responses that are responsible for transplant rejection are
directed against differences in the MHC molecules.
...
There are three main types of cells in the blood:
[-] Leukocytes or white blood cells, these are nucleated cells that play
various roles in immune defense and inflammation.
[-] Erythrocytes or red blood cells, these are small cells that do not have
nuclei and contain molecules (hemoglobin) that function as carriers of oxygen
and carbon dioxide.
[-] Platelets, that are fragments of a bone marrow precursor cell called
megakaryocyte and that are important in coagulation.
These cells, apart from their functions, are structurally different, and in
view of the expression of MHC molecules: leukocytes express them in high
levels, platelets express predominantly low levels of Class I MHC antigens,
and red blood cells do not express them at all. Thus, a normal rejection
process operates for leukocytes and platelets after a blood transfusion."
Because of rejection, most blood transfusions are "packed cell transfusions,"
that is almost totally red blood cells, and if it is whole blood, then it is
either Type O ("universal") or type matched.
If you need any any clarification, please feel free to ask.
Search strategy:
Google search on: blood transfusion rejection
://www.google.com/search?q=blood+transfusion+rejection
Google search on: blood transfusion DNA
://www.google.com/search?q=blood+transfusion+DNA
Looking Forward, denco-ga - Google Answers Researcher |
