title: Forensic mitochondrial DNA analysis of 691 casework hairs.
abstract: A five year retrospective review of mitochondrial DNA (mtDNA) analysis on 691 casework hairs was carried out. A full or partial mtDNA profile was obtained for > 92% of hairs. With increasing age of the hair, the likelihood of obtaining a full profile decreased, although "mini-primer sets" could often be used to capture a partial profile. With increasing color and diameter of the hair, the likelihood of obtaining a profile increased. Full or partial profiles were obtained on more than 80% of 114 hairs < or = 1.0 cm. Mixtures were observed in 8.7% of hairs tested; mixtures increased with the age of the hair and were presumed to be due to exterior surface contamination that could not be sufficiently cleaned prior to extraction, since the overall level of laboratory contamination was low. The frequency of sequence heteroplasmy was 11.4%, and both hot-spot and novel sites were observed. In about one-third of these observations, another sample in the case showed either the same heteroplasmic site or a nucleotide substitution at that site.
authors.affiliation: Mitotyping Technologies, 2565 Park Center Boulevard, Suite 200, State College, PA 16801, USA.
authors.forename: Terry
authors.initials: T
authors.lastname: Melton
authors.forename: Gloria
authors.initials: G
authors.lastname: Dimick
authors.forename: Bonnie
authors.initials: B
authors.lastname: Higgins
authors.forename: Lynn
authors.initials: L
authors.lastname: Lindstrom
authors.forename: Kimberlyn
authors.initials: K
authors.lastname: Nelson
mesh_terms: D016172:DNA Fingerprinting; D004272:DNA, Mitochondrial / Q000032:analysis*; D005554:Forensic Medicine / Q000379:methods; D006197:Hair / Q000737:chemistry*; D006801:Humans; D012189:Retrospective Studies; D013048:Specimen Handling
chemical_list: D004272:DNA, Mitochondrial