Trial Lecture - time and place
See Trial Lecture.
Adjudication Committee
- 1st opponent: Associated Researcher Lourdes Prieto Solla, University of Santiago de Compostela
- 2nd opponent: Researcher Johannes Hedman, Lund University
- Committee Chair: Professor Benedicte Alexandra Lie, University of Oslo
Chair of the Defence
Professor Lars Eide
Principal Supervisor
Adjunct Professor Peter Gill
Summary
DNA profiling has revolutionised forensic science as a powerful tool in criminal investigations. Court decisions can have an enormous impact on a person’s life. It is therefore essential to characterise the molecular biology processes used in forensic DNA profiling assays to define its limitations and ensure confident interpretation.
Knowledge is acquired through validation of the DNA analysis kit. Traditionally, it has been both time-consuming and resource-intensive. Published data often use different kinds of statistics, preventing direct comparisons of validations.
The aims of the thesis were to approach this problem by developing software packages to 1) automate characterisation of forensic STR DNA profiling assays and 2) simulate the molecular biology processes used.
We developed the free and open source computer software STR-validator to contribute to standardisation and improved quality of validation while allowing laboratories to greatly reduce the time spent analysing data, and PCR-sim to simulate the entire DNA analysis process.
Benefits of using STR-validator was exemplified by exploratory analysis of validation data and comparison to published results. Amplification of low-template and degraded samples were simulated using PCR-sim to explore the heterozygote balance of diploid and haploid cells and the results were compared to empirical data. By exploiting information from today's standard quantification kits, it is possible to predict the outcome of the DNA profile. Negative controls collected from the routine DNA analysis process was analysed to identify possible artefacts and contamination. Single molecule amplification was performed to support the underlying theory.
STR-validator is widely used, promoting faster implementation of new and better DNA profiling kits worldwide. Simulations can be used to optimise analysis of essential casework samples, and to explore properties of samples that are difficult to create in the laboratory.
Additional information
Contact the Research Support Staff.