A series of five talks on the forensic evaluation of Y-profile (and mtDNA) evidence.

Mikkel Meyer Andersen (Aalborg University, Denmark)
David Balding (University of Melbourne, Australia)

Last updated: Aug 6, 2020.

Welcome to a series of 5 talks introducing a better way to report to a court the significance of matching Y-chromosome profiles between an evidence sample and its alleged source. The presenters are David Balding (University of Melbourne, Australia) and Mikkel M. Andersen (Aalborg University, Denmark).

Our new method complements previous approaches, for example based on computing a match probability: the new method becomes increasingly advantageous as Y-profiles become more informative (more loci, higher mutation rates).

Talk 1 presents the basic method and we recommend it be viewed first, the other four talks can then be viewed in any order. The series is intended for forensic scientists and others in the criminal justice system who encounter DNA evidence. Little scientific background is required for these talks, technical details are in scientific publications.

Note that all videos are available at our YouTube channel Y-talks 2020 by M. M. Andersen and D. Balding.

We invite you to use the Discussion feature of YouTube (available at each talk). You are also welcome to send us an e-mail (mikl{a}math.aau.dk / dbalding{a}unimelb.edu.au).

We would like to thank Andrew McDonald (Cellmark Forensic Services, currently at PathWest) for encouragement, feedback and help with dissemination.

1. A new approach to Y profile evaluation

38 mins

Key reference: Andersen MM, Balding D (2017). How convincing is a matching Y-chromosome profile? PLoS Genetics, 3(11): e1007028, DOI: 10.1371/journal.pgen.1007028

2. Introduction to the malan (MAle Lineage ANalysis) R package.

27 mins

Key reference: Andersen MM (2018). malan: MAle Lineage ANalysis. Journal of Open Source Software, 3(25), 684, DOI: 10.21105/joss.00684

3. Y-profile mixtures and profiled relatives.

20 mins

Key reference: Andersen MM, Balding D (2019). Y-profile evidence: close paternal relatives and mixtures. Forensic Science International: Genetics, 38: 48-53, DOI: 10.1016/j.fsigen.2018.10.004

4. Using the Discrete Laplace method to compute a Y-profile match probability.

39 mins

Key reference: Andersen MM, Eriksen PS, Morling N (2013). The discrete Laplace exponential family and estimation of Y-STR haplotype frequencies. Journal of Theoretical Biology, 329: 39-51, DOI: 10.1016/j.jtbi.2013.03.009

5. The number of matches for a mitochondrial genome.

22 mins

Key reference: Andersen MM, Balding D (2018). How many individuals share a mitochondrial genome? PLoS Genetics, 14(11): e1007774, DOI: 10.1371/journal.pgen.1007774