Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

With which bacterial infection in humans has it been shown that bacterial DNA can be found in the blood?

If any is found it is likely not to be very much, and even difficult to distinguish from human DNA, but presumably recent advances in sequencing should have made it possible.

share|improve this question
Even difficult to distinguish from human DNA. Hmmm... a simple PCR for a bacterial-specific gene would easily distinguish human from bacterial DNA. – nico Jul 11 '12 at 11:56
Yeah I think qPCR is a fairly routine diagnostic for determining a strain. – Ben Jul 11 '12 at 12:56
@nico so which exclusively bacterial gene would you pick out? – rwst Aug 1 '12 at 15:06
@rwst: hmmm... I'm sure there are tons of them. 16S for bacteria vs 18s for human would be easy enough. – nico Aug 1 '12 at 15:33
up vote 4 down vote accepted

Everything depends upon the infection and on the general immune status of the patient.

Generally, the prerequisite for DNA to freely circulate in the blood is the presence of bacteria themselves in the blood (bacteraemia). This means that the infection left its original site (where it is usually kept isolated from the blood flow by the immune system). Depending upon the body reaction to this breakthrough, sepsis and/or SIRS can be the consequences.

Under these conditions (not necessarily as severe as sepsis, but in case of proven bacteriemia), the bacteria cells get attacked by the immuno cells, that leads to their eventual lyzing and releasing their content to the blood.

PCR can be used as a method to prove the existence of bacterial DNA. (Here is a publicly available paper on this topic).

share|improve this answer
Thanks for the ref. Barbars are they, let the rats gulp CCl4, nasty stuff... – rwst Aug 1 '12 at 15:01

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.