Author/Editor		Inkret, Jezerka; Podovšovnik, Eva; Zupanc, Tomaž; Zupanič-Pajnič, Irena
Title		Nails as a primary sample type for molecular genetic identification of highly decomposed human remains
Type		članek
Publication year		2020
Volume		str. str.
ISSN		0937-9827 - International journal of legal medicine
Language		eng
Abstract		For identification of badly preserved cadavers, only a few tissues can be used as a source of DNA, mostly bones and teeth, from which sampling and DNA extraction are difficult and time-consuming. In most highly decomposed remains, the nails are preserved. The aim of this study was to evaluate nails as an alternative source of DNA instead of bones and teeth in demanding routine identification cases. An automated extraction method was optimized on nails obtained from 33 cadavers with a post-mortem interval (PMI) up to 5 years. The commercially available EZ1 Investigator Kit (Qiagen) was used for extraction, and the G2 buffer included in the kit was replaced with TNCa buffer, and DTT was added for digestion of 5 mg of nail. The DNA was purified in a Biorobot EZ1 device (Qiagen), quantified using the PowerQuant System (Promega), and STR typing was performed with the NGM kit (TFS). From 0.3 to 270 %g DNA/g of nail was obtained from the samples analyzed, with an average yield of 36 %g DNA/g of nail. Full STR profiles were obtained from all nails except one. The optimized extraction method proved to be fast and highly efficient in the removal of PCR inhibitors, and it yields high amounts of DNA for successful STR typing. Nails were implemented as the primary sample type for obtaining DNA from highly decomposed and partially skeletonized cadavers in routine forensic identification cases in our laboratory.
Keywords		nails DNA extractionmethod human identification nohti metoda ekstrakcije DNK človeška identifikacija