Expert Systems inDNAInterpretation

Abstract

Expert systems have been developed as specialized software that can assist forensic scientists to interpret complex DNA profiles. These software allow the evaluation of the weight of the DNA evidence within a likelihood ratio framework, and they are particularly helpful to analyze low‐template DNA mixtures. In this review, we describe the expert systems that have recently become available. We discuss the theoretical principles and advantages and limitations of these systems, along with aspects of performance and validation.

Evaluation of samples comprising minute amounts of DNA

“…From our results (that used a discrete/semi-continuous LR model), we conclude that when the relevance of the evidence is weak, it may be best to decide not to continue to computing an LR, even though it could result in a large LR in favour of the prosecution hypothesis. The specifics of the LR-based statistical model (such as the choice between a continuous and semi-continuous model that make yes or no use of peak height information) that is applied, will affect the actual LR that is obtained [23,[35][36][37][38][39]. The suitability of using peak height information in profiles derived with enhanced interrogation techniques has, however, not been shown.…”

Integrated Polymerase Chain Reaction Technologies (Sample-to-Answer Technologies)

“…The use of short tandem repeats (STRs) as target genetic markers and the highly variable nature of forensic evidence with regard to sample integrity, DNA quantity, and contributor complexity make data interpretation an especially time-and labor-intensive process, requiring manual review by a skilled laboratory analyst. Efforts to streamline this process have focused on the development of powerful expert systems (computer software that is guided by user-defined rules with the goal of being able to consistently analyze a given set of data with the same skill as a human) (Haned and Gill, 2015). Expert systems do not replace humans.…”