Get it off, but keep it: Efficient cleaning of hair shafts with parallel DNA extraction of the surface stain

Publication date: Available online 26 November 2019Source: Forensic Science International: GeneticsAuthor(s): Jana Naue, Timo Sänger, Sabine Lutz-BonengelAbstractThe analysis of hair samples is a common task in forensic investigations. Material transferred to the surface of a hair during a crime challenges the analysis as it has to be removed efficiently. However, the removal of the stain can also lead to a loss of information on stain contributors. DNA analysis of the stain itself might thus be helpful for the forensic investigation. The aim of this study was the examination of different methods to remove common biological surface stains completely from human hair shafts without hampering the parallel DNA extraction of the cleaned hair shaft and the isolated surface stain (blood, saliva, vaginal secretion, semen, and skin flocks). Four different methods of cleaning (water, lysis buffer, swabbing, NaClO) were compared to their cleaning efficiency as well as their success of mtDNA analysis of three hair donors and the original five stains on the hair. In order to test the suitability of this procedure for future analysis methods, a selection of samples were also sequenced with MPS. Additionally, nuclear DNA analysis of the stain DNA was performed using a screening STR assay to test the potential success for detection of a STR profile.The most efficient removal of the stain was achieved using NaClO, however compromising further analysis of the stain DNA. The best results for c...
Source: Forensic Science International: Genetics - Category: Forensic Medicine Source Type: research