NCJ Number
225666
Journal
Forensic Science International: Genetics Volume: 3 Issue: 1 Dated: December 2008 Pages: 46-49
Date Published
December 2008
Length
4 pages
Annotation
This study evaluated the use of fingernails as an alternative DNA source for the genetic identification of decomposed cadavers.
Abstract
The study found that nails are easy to collect and contain large amounts of good quality DNA that can be extracted within a few hours. They thus provide an attractive DNA source for standard and urgent identification of decomposed corpses, providing exogenous DNA contaminants are limited. Large amounts of DNA were recovered from fingernails. DNA extracts with concentrations that ranged from 4.5 to 173.6 ng/ml were obtained for the seven volunteers, using 5-50 mg of nail after overnight lyses. This represents an average of 54.1 ng DNA/mg mail. As expected, DNA concentration linearly increased with the amount of nail used for the extraction. Between 4.5 and 36.2 ng/ml DNA was recovered using 5 mg of nail and the fast DNA extraction protocol with 1 hour lysis. DNA concentrations obtained from 5 mg of fingernails collected on 10 corpses ranged from 2.5 to 222.7 and 0.6 to 47.2 ng/ml for the standard and fast DNA extraction protocols, respectively. Full DNA profiles were obtained for all corpses, independently of lysis time, postmortem interval, and the environment in which the body was found. DNA profiles from fingernails and from other biological material (blood, muscle, or bone) collected on the deceased were similar. No mixed DNA profile was observed. Fingernails were cut with scissors from fresh cadavers and from seven volunteers. Nails were quickly washed before analyses in order to remove any exogenous or endogenous DNA from other biological material. DNA was then extracted with the use of a lysis buffer and purified with QIAamp DNA minikit columns. 1 table, 2 figures, and 19 references