Invasive Genes: Humans incorporate DNA from parasite

The “us-against-them” mindset may take on new meaning when applied to infections by the parasitic protozoan Trypanosoma cruzi. New research shows that bits of foreign DNA from the parasite become integrated into the DNA of an infected person. This is the first time that parasitic DNA has been found in the human genome, says Antonio Teixeira of the University of Brasilia in Brazil.