title: Mass-Spectrometry-Based Proteomics Reveals Organ-Specific Expression Patterns To Be Used as Forensic Evidence.
abstract: Standard forensic procedures to examine bullets after an exchange of fire include a mechanical or ballistic reconstruction of the event. While this is routine to identify which projectile hit a subject by DNA analysis of biological material on the surface of the projectile, it is rather difficult to determine which projectile caused the lethal injury--often the crucial point with regard to legal proceedings. With respect to fundamental law it is the duty of the public authority to make every endeavor to solve every homicide case. To improve forensic examinations, we present a forensic proteomic method to investigate biological material from a projectile's surface and determine the tissues traversed by it. To obtain a range of relevant samples, different major bovine organs were penetrated with projectiles experimentally. After tryptic "on-surface" digestion, mass-spectrometry-based proteome analysis, and statistical data analysis, we were able to achieve a cross-validated organ classification accuracy of >99%. Different types of anticipated external variables exhibited no prominent influence on the findings. In addition, shooting experiments were performed to validate the results. Finally, we show that these concepts could be applied to a real case of murder to substantially improve the forensic reconstruction.
authors.affiliation: Institute for Ophthalmic Research, Medical Proteome Center, University Hospital Tuebingen , Naegelestrasse 5, 72074 Tuebingen, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Dammeier
authors.affiliation: Quantitative Biology Center, Eberhard Karls University of Tuebingen , Auf der Morgenstelle 10, 72076 Tuebingen, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Nahnsen
authors.affiliation: Center for Bioinformatics and Department of Computer Science, Eberhard Karls University of Tuebingen , Sand 14, 72076 Tuebingen, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Veit
authors.affiliation: Institute for Forensic Medicine, Eberhard Karls University of Tuebingen , Naegelestrasse 5, 72074 Tuebingen, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Wehner
authors.affiliation: Institute for Ophthalmic Research, Medical Proteome Center, University Hospital Tuebingen , Naegelestrasse 5, 72074 Tuebingen, Germany.
authors.forename: Marius
authors.initials: M
authors.lastname: Ueffing
authors.affiliation: Quantitative Biology Center, Eberhard Karls University of Tuebingen , Auf der Morgenstelle 10, 72076 Tuebingen, Germany.|Center for Bioinformatics and Department of Computer Science, Eberhard Karls University of Tuebingen , Sand 14, 72076 Tuebingen, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Kohlbacher
mesh_terms: D000818:Animals; D001930:Brain Injuries / Q000175:diagnosis; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D017809:Fatal Outcome; D005260:Female; D044709:Forensic Ballistics; D006708:Homicide / Q000331:legislation & jurisprudence; D006801:Humans; D008297:Male; D008875:Middle Aged; D009928:Organ Specificity; D020543:Proteome / Q000737:chemistry* / Q000302:isolation & purification; D040901:Proteomics / Q000379:methods; D053719:Tandem Mass Spectrometry; D014948:Wounds, Gunshot / Q000175:diagnosis*
chemical_list: D020543:Proteome
keywords: PCA; bottom-up proteomics; data classification; forensic medicine; machine learning algorithm; projectile