Lessons from a study of DNA contaminations from police services and forensic laboratories in Switzerland.

Détails

Ressource 1Télécharger: 29275090_pp_cover.pdf (785.08 [Ko])
Etat: Serval
Version: Author's accepted manuscript
Licence: CC BY-NC-ND 4.0
ID Serval
serval:BIB_F05DA40ACF83
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Lessons from a study of DNA contaminations from police services and forensic laboratories in Switzerland.
Périodique
Forensic science international. Genetics
Auteur(s)
Basset P., Castella V.
ISSN
1878-0326 (Electronic)
ISSN-L
1872-4973
Statut éditorial
Publié
Date de publication
03/2018
Peer-reviewed
Oui
Volume
33
Pages
147-154
Langue
anglais
Notes
Publication types: Journal Article
Publication Status: ppublish
Résumé
In Switzerland, the DNA profiles of police officers collecting crime scene traces as well as forensic genetic laboratories employees are stored in the staff index of the national DNA database to detect potential contaminations. Our study aimed at making a national inventory of contaminations to better understand their origin and to make recommendations in order to decrease their occurrence. For this purpose, a retrospective questionnaire was sent to both police services and forensic genetic laboratories for each case where there was a contamination. Between 2011 and 2015, a total of 709 contaminations were detected. This represents a mean of 11.5 (9.6-13.4) contaminations per year per 1'000 profiles sent to the Swiss DNA database. Feedbacks were obtained from the police, the laboratory or both for 552/709 (78%) of the contaminations. Approximately 86% of these contaminations originated from police officers whereas only 11% were from genetic laboratories employees and 3% were associated to other sources (e.g. positive controls, stain-stain contaminations). Interestingly, a direct contact between the stain and the contaminant person occurred in only 51% of the laboratory contaminations whereas this number increased to 91% for police collaborators. The high level of indirect DNA transfer in laboratories might be explained by the presence of "DNA reservoirs" suggesting that cleaning procedures should be improved. At the police level, most contaminations originated from the person who collected the trace and likely occurred directly at the crime scene. Improving sampling practices could be beneficial to reduce these contaminations.
Mots-clé
DNA Contamination, Humans, Laboratories/statistics & numerical data, Police/statistics & numerical data, Retrospective Studies, Surveys and Questionnaires, Switzerland, DNA contamination, Forensic DNA analysis, Recommendations, Transfer
Pubmed
Web of science
Open Access
Oui
Création de la notice
08/01/2018 12:43
Dernière modification de la notice
13/07/2019 16:15
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