title: The Use of Laser Microdissection in Forensic Sexual Assault Casework: Pros and Cons Compared to Standard Methods.
abstract: Sexual assault samples are among the most frequently analyzed in a forensic laboratory. These account for almost half of all samples processed routinely, and a large portion of these cases remain unsolved. These samples often pose problems to traditional analytic methods of identification because they consist most frequently of cell mixtures from at least two contributors: the victim (usually female) and the perpetrator (usually male). In this study, we propose the use of current preliminary testing for sperm detection in order to determine the chances of success when faced with samples which can be good candidates to undergo analysis with the laser microdissection technology. Also, we used laser microdissection technology to capture fluorescently stained cells of interest differentiated by gender. Collected materials were then used for DNA genotyping with commercially available amplification kits such as Minifiler, Identifiler Plus, NGM, and Y-Filer. Both the methodology and the quality of the results were evaluated to assess the pros and cons of laser microdissection compared with standard methods. Overall, the combination of fluorescent staining combined with the Minifiler amplification kit provided the best results for autosomal markers, whereas the Y-Filer kit returned the expected results regardless of the used method.
authors.affiliation: Department of Legal Medicine and Forensic Sciences, Faculty of Medicine, University of Porto, Porto, Portugal.|North Department, National Institute of Legal Medicine and Forensic Sciences, Oporto, Portugal.
authors.forename: Sergio
authors.initials: S
authors.lastname: Costa
authors.affiliation: Laboratório de Farmacologia e Neurobiologia - Center for Drug Discovery and Innovative Medicines (MedInUP), Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Porto, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Correia-de-Sá
authors.affiliation: North Department, National Institute of Legal Medicine and Forensic Sciences, Oporto, Portugal.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Porto
authors.affiliation: Department of Legal Medicine and Forensic Sciences, Faculty of Medicine, University of Porto, Porto, Portugal.|North Department, National Institute of Legal Medicine and Forensic Sciences, Oporto, Portugal.
authors.forename: Laura
authors.initials: L
authors.lastname: Cainé
mesh_terms: D004247:DNA / Q000032:analysis; D016172:DNA Fingerprinting; D005260:Female; D005453:Fluorescence; D005554:Forensic Medicine / Q000379:methods*; D005838:Genotype; D006801:Humans; D007834:Lasers; D008297:Male; D042282:Microdissection; D016133:Polymerase Chain Reaction; D012742:Sex Offenses; D013094:Spermatozoa / Q000737:chemistry* / Q000166:cytology*; D013194:Staining and Labeling
chemical_list: D004247:DNA
keywords: Sperm Hy-Liter Express; forensic science; laser microdissection; sexual assault