- •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.
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.
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Published online: October 31, 2014
Accepted: October 23, 2014
Received: September 30, 2014
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