The properties of cells and DNA are manipulated to isolate the DNA from
the nuclei of cells that have been collected. Cells are lysed (burst)
open and then unnecessary things like proteins and lipids (fats) and
other cellular debris are removed until we are left with pure DNA. As
you can imagine, though, since the cells are shed with the feces, there
actually are not that many of them, and so the amount of DNA that is
actually isolated may be small.
