Use of DNA profiles for investigation using a simulated national DNA database: Part I. Partial SGM Plus® profiles

Hicks, T.; Taroni, F.; Curran, J.; Buckleton, J.; Ribaux, O.; Castella, V.

doi:10.1016/j.fsigen.2009.10.002

« Previous Next »Forensic Science International: Genetics
Volume 4, Issue 4 , Pages 232-238, July 2010

Use of DNA profiles for investigation using a simulated national DNA database: Part I. Partial SGM Plus^® profiles

T. Hicks
- School of Criminal Justice, University of Lausanne, Batochime, 1015 Lausanne Dorigny, Switzerland
- Corresponding author at: School of Criminal Justice, Institut de police scientifique, University of Lausanne, Batochime, 1015 Lausanne Dorigny, Vaud, Switzerland. Tel.: +41 21 692 46 51; fax: +41 21 692 46 05.
F. Taroni
- School of Criminal Justice, University of Lausanne, Batochime, 1015 Lausanne Dorigny, Switzerland
J. Curran
- Department of Statistics, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
J. Buckleton
- ESR Ltd., Private Bag 92-021, Auckland Mail Centre, Auckland 1142, New Zealand
O. Ribaux
- School of Criminal Justice, University of Lausanne, Batochime, 1015 Lausanne Dorigny, Switzerland
V. Castella
- Forensic Genetics Unit, University Center of Legal Medicine, West Switzerland, Rue du Bugnon 21, 1011 Lausanne, Switzerland

Received 24 February 2009; received in revised form 17 August 2009; accepted 2 October 2009. published online 04 November 2009.

Abstract

In traditional criminal investigation, uncertainties are often dealt with using a combination of common sense, practical considerations and experience, but rarely with tailored statistical models. For example, in some countries, in order to search for a given profile in the national DNA database, it must have allelic information for six or more of the ten SGM Plus^® loci for a simple trace. If the profile does not have this amount of information then it cannot be searched in the national DNA database (NDNAD). This requirement (of a result at six or more loci) is not based on a statistical approach, but rather on the feeling that six or more would be sufficient. A statistical approach, however, could be more rigorous and objective and would take into consideration factors such as the probability of adventitious matches relative to the actual database size and/or investigator's requirements in a sensible way. Therefore, this research was undertaken to establish scientific foundations pertaining to the use of partial SGM Plus^® loci profiles (or similar) for investigation.

Keywords: DNA evidence, National DNA databases, Partial profiles, Investigation, Likelihood ratio