DNA suitable for the most common variety of forensic testing is found within cells in the human body.  The human body is rich with cellular material as there are trillions of cells that make up the human anatomy.  Most of our body parts contain cells with nuclei.  It is within the nucleus of the cell that the DNA resides. This so-called nuclear DNA is the focus of most forensic typing.

There are areas in and on the body that do not contain nuclear DNA.  Within blood, it is the white blood cells that contain DNA, as red blood cells are actually anucleated.  The cellular material in hair shafts does not contain an appreciable amount of nuclear DNA.  If hair evidence is to be used for DNA typing, there must be root material attached to provide the nuclear DNA.  Finally, some skin cells are anucleated or may be dried out to…