Highlights
- •Fluorescence-assisted cell sorting (FACS) of mixedfresh blood/saliva was trialled.
- •Previously undetectable alleles in various ratios of mixtures detected after sorting.
- •Probative values strengthened considerably after FACS sorting.
- •Use of FACS before extraction may improve probative value of forensic analysis.
- •Research on compromised samples required before FACS adopted by forensic labs.
Abstract
Although focusing attention on the statistical analysis of complex mixture profiles
is important, the forensic science community will also benefit from directing research
to improving the reduction of the incidence of mixtures before DNA extraction. This
preliminary study analysed the use of fluorescence assisted cell sorting (FACS) for
separation of cellular mixtures before DNA extraction, specifically mixtures of relatively
fresh blood and saliva from two donors, prepared in 14 different mixture ratios. Improvements
in the number of detectable alleles from the targeted cell type and overall profile
quality were seen when compared to the results from unseparated samples. STRmix calculations
revealed increases in likelihood ratios after separation, demonstrating the potential
for higher probative values to be obtained from forensically relevant mixtures after
subjecting them to FACS than from unsorted samples.
Keywords
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Article info
Publication history
Published online: October 31, 2014
Accepted:
October 23,
2014
Received:
September 30,
2014
Identification
Copyright
© 2014 Elsevier Ireland Ltd. Published by Elsevier Inc. All rights reserved.
