Identification using DNA from skin contact: case reports.
The DNA content of different types of forensic materials can vary substantially. "Trace DNA" is the minute quantity of DNA transferred through skin contact. Here, we report three cases of identification of trace DNA using conventional short tandem repeat (STR) or mitochondrial DNA (mtDNA). DNA was successfully obtained from fabrics by swabbing or by direct extraction and subjected to STR genotyping or mtDNA typing. In two cases, there was no amplification of PCR products containing the STR loci. This indicates that the areas chosen for DNA extraction contained trace DNA and DNA from more than one source. Therefore, it is important for forensic investigators performing DNA typing to know where an item has been frequently touched by victims and/or offenders as this will influence the choice of sites on the item to be used for DNA extraction.
Tokutomi
Tomoharu
T
Department of Forensic Medicine, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan. dr20002@ndmc.ac.jp
Takada
Yuzo
Y
Kanetake
Jun
J
Mukaida
Masahiro
M
D003020:Clothing; D003415:Crime; D016172:DNA Fingerprinting / Q000379:methods*; D004272:DNA, Mitochondrial / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D020080:Tandem Repeat Sequences; D014110:Touch
D004272:DNA, Mitochondrial