title: Analysis and interpretation of mixed forensic stains using DNA STR profiling.
abstract: The use of multiplex PCR and fluorescent dye technology in the automated detection and analysis of short tandem repeat loci provides not only qualitative information about the profile--i.e. which alleles are present--but can also provide quantitative information on the relative intensities of the bands, and is therefore a measure of the amount of amplified DNA. The availability of this quantitative information allows for the interpretation of mixtures in a detailed way which has not been previously possible with many other human identification systems. In this paper we present a simple approach to the resolution and analysis of mixed STR profiles resulting from the testing of mixed biological stains in forensic casework and highlight factors which can affect it. This approach requires a detailed knowledge--gained through a mixture of experiments and validation studies--of the behaviour of each locus within the multiplex systems described. We summarise the available data from previously published experimental work and validation studies to examine the general principles underlying this approach.
authors.affiliation: Forensic Science Service, Wetherby Laboratory, West Yorkshire, UK.
authors.forename: T M
authors.initials: TM
authors.lastname: Clayton
authors.forename: J P
authors.initials: JP
authors.lastname: Whitaker
authors.forename: R
authors.initials: R
authors.lastname: Sparkes
authors.forename: P
authors.initials: P
authors.lastname: Gill
mesh_terms: D000483:Alleles; D004247:DNA / Q000032:analysis* / Q000235:genetics; D017931:DNA Primers / Q000737:chemistry; D005260:Female; D005456:Fluorescent Dyes; D005554:Forensic Medicine / Q000379:methods*; D005819:Genetic Markers / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D015203:Reproducibility of Results
chemical_list: D017931:DNA Primers; D005456:Fluorescent Dyes; D005819:Genetic Markers; D004247:DNA