DNA, an acronym for Deoxyribonucleic Acid, is the genetic material that is found in the nucleus of most cells in the human body (nuclear DNA). DNA is also found in the energy-producing mitochondria contained within every cell in the human body (mitochondrial DNA).

Other important facts about DNA include:
- The same copy of DNA is present in all cells
- There are estimated to be 10-100 trillion cells in the human body
- Most common DNA identity test uses nuclear DNA from cheek cells
- Bone, hair, blood are examples of other sample types