Discrimination between human and animal DNA: application of a duplex polymerase chain reaction to forensic identification.
Identification of a report's species is one of the basic analyses in forensic laboratories. The authors report the case of 6 bone fragments recovered in a wooded area, which were not attributable to 1 animal species on the basis of morphologic examination. The aim of this study was to develop a duplex polymerase chain reaction (PCR) to discriminate human and animal origin of bone fragments. The method is based on the PCR amplification of cytochrome b and a 16S ribosomal mitochondrial DNA fragment, which has never been tested up to now. Our protocol combines a single-round PCR with direct visualization of amplicons in agarose gel, without sequencing analysis of the PCR products. The presence of a single band (359 bp) indicates a nonhuman origin of the sample, whereas 2 bands (157 and 359 bp) indicate a human biologic sample.This method revealed to be useful for forensic purposes because the 16S ribosomal mitochondrial DNA is a small human-specific fragment that is easily amplifiable even with degraded DNA from biologic materials such as old bones.
Department of Environmental Medicine and Public Health, Legal Medicine Section, University of Padua, Padova, Italy.
Pamela
P
Tozzo
Elena
E
Ponzano
Enrico
E
Novelli
Maurizio
M
Onisto
Luciana
L
Caenazzo
D000818:Animals; D045303:Cytochromes b / Q000235:genetics*; D053836:DNA Degradation, Necrotic; D004272:DNA, Mitochondrial / Q000235:genetics*; D004587:Electrophoresis, Agar Gel; D053803:Forensic Genetics / Q000379:methods; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013045:Species Specificity
D004272:DNA, Mitochondrial; D012336:RNA, Ribosomal, 16S; D045303:Cytochromes b