100 identification markers for hair identification, this would be sufficient to get a unique pattern to get a person out of the entire world's population. >> there's an individual peptide that's coming out of the chromatograph. this represents each peptide that comes out. >> reporter: the vallejo is how robust it is. -- the advantage is how robust it is. think of the hair balls under your bed. it's easily mixed up in a messy scene. >> you come across the crime scene. it may not be just one person's blood in a pool of blood. but the more contributors to the mixture of dna, the more difficult it is to determine whose dna it was, whose blood it was. the nice thing about hair, it only came from one person. >> reporter: scientists have been able to test a piece of hair for markers over 250 years old. breaking the hair down and giving a profile is almost as