DNA

Trace amounts of DNA were recovered from various items at the scene. The DNA overwhelmingly belonged to JonBenet Ramsey herself, however some mixed profiles contained unidentified components. Some argue that one or more of these identified profiles belongs to an intruder or intruders who were in the home on the night of JonBenet's death. This theory has been contested by Boulder Police and independent scientists consulted by the Boulder Daily Camera, however it has been supported by the Ramseys' lawyers and some investigators from the District Attorney's office.

The underwear DNA
Timeline of DNA Testing of the underwear

1997 — DNA collected from a blood spot on JonBenet Ramsey’s underwear described as contaminated.

1999 — FBI releases new technology called Short Tandem Repeat to profile DNA. It uses 13 markers to raise the probability that a randomly selected individual would match it is one in 1 quintillion.

2001 — The new testing is allowed after a legal battle in Colorado’s courts, and JonBenet’s underwear is analyzed again resulting in between one and two markers out of 13 being defined.

2003 — Second blood spot on JonBenet’s underwear tested resulting in between nine and 10 markers on the spot to be defined. That genetic fingerprint meets the threshold to be placed into a national database, Combined DNA Indexing System or CODIS, which holds DNA profiles of those convicted in most states of certain crimes. No match has been made.

2008 - Bode Laboratories testing