Highlights
- •Forensic Science SA implemented STRmix™ in 2012.
- •STRmix™ has deconvoluted all mixed DNA profiles at FSSA since implementation.
- •All 2019 STRmix™ analyses were interrogated to identify trends across the dataset.
- •All pairwise comparisons of deconvolutions identified common DNA donors.
- •32 groups of linked cases were identified and could be used as police intelligence.
Abstract
Forensic Science South Australia (FSSA) has been using STRmix™ software to deconvolute
all reported DNA mixtures since 2012. Almost a decade of deconvolutions had led to
a substantial repository of analysed profile data that can be interrogated to observe
trends in case type, location or occurrence. In addition, deconvolutions can be compared
in order to identify common DNA donors and reveal new intelligence information in
cases where DNA profiling has previously provided no investigative information. As
a proof of concept all samples deconvoluted as part of criminal casework (suspect
or no-suspect) were interrogated and compared to each other using the mixture-to-mixture
comparison feature in STRmix™. Within the Adelaide region there were 32 groups of
cases that had evidence samples linked by a common DNA donor with LR > 1 million which was in addition to direct links and mixture searching links identified
previously. These groups of cases can then be interrogated to reveal additional information
to inform Police intelligence gathering. Our paper reports on the findings of this
proof-of-concept study.
Keywords
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Article info
Publication history
Published online: November 20, 2021
Accepted:
November 6,
2021
Received in revised form:
October 2,
2021
Received:
June 24,
2021
Identification
Copyright
© 2021 Elsevier B.V. All rights reserved.
