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Probabilistic Genotyping of Evidentiary DNA Typing Results - Module 7: Uncertainty and Limitations of Probabilistic Genotyping Systems

Event Dates
Event Duration
4 hours

Has a person of interest contributed DNA to a mixture obtained from evidence? Is that DNA associated with a crime? Both are questions that cannot be answered with absolute certainty. This module of the Probabilistic Genotyping of Evidentiary DNA Typing Results workshop series addresses the uncertainty and limitations of probabilistic genotyping systems that are used to calculate likelihood ratios and infer genotype sets from DNA typing results. Probabilistic reasoning provides a means to characterize these results, given the unknown information in forensic evidence, the stochastic environment, and sources of variability. Instructors in Module 7 will explore strategies of interpretation and decision making in light of these and other variables, such as the uncertain number of contributors, and will share research on the impact of these variables on the likelihood ratio.

Additionally, courts are becoming increasingly interested not just in “whose DNA is this?” but “how did the DNA get there?” Therefore, the instructors will revisit topics introduced earlier in the series to dive deeper into the relevance of a DNA profile, given today’s advanced detection sensitivity and the potential for DNA transfer, as well as activity level reporting and the hierarchy of propositions.

Amke Caliebe – University of Kiel, Kiel, Germany
Zane Kerr – Institute on Environmental Science and Research, Auckland, New Zealand
Klaas Slooten – Netherlands Forensic Institute & Vrije University, Amsterdam, The Netherlands
Bianca Szkuta – Victoria Police Forensic Services Department & Deakin University, Geelong, Australia

Date Created: August 8, 2019