You can tell a lot by fingerprints, from who you are, to who you are related to, to even being able to convict you for a crime. DNA testing is very accurate, the chances of inaccuracy is 1 in a billion. People can have similar DNA when tested by swabs, blood, or urine. With fingerprinting you are able to pinpoint a particular person because there is only one set of your fingerprints, your own! A DNA fingerprint is the same for every cell, tissue, and organ of a person. It cannot be altered by any treatment. DNA fingerprinting is the primary method for distinguishing human beings.
http://www.iiiweb.net/forensic-services/crime-scene-investigations/