DNA fingerprint. Conceptual computer artwork of a bar code and a human fingerprint, representing the technique of DNA fingerprinting. DNA (deoxyribo- nucleic acid) is genetic material that contains instructions for the development and functioning of all living organisms. Each cell of the human body contains DNA in the form of chromosomes. DNA fingerprinting is a diagnostic technique used to identify individuals from samples of their DNA. It involves the examination of regions of DNA known to be unique for each person.