title: Population-specific FST values for forensic STR markers: A worldwide survey.
abstract: The interpretation of matching between DNA profiles of a person of interest and an item of evidence is undertaken using population genetic models to predict the probability of matching by chance. Calculation of matching probabilities is straightforward if allelic probabilities are known, or can be estimated, in the relevant population. It is more often the case, however, that the relevant population has not been sampled and allele frequencies are available only from a broader collection of populations as might be represented in a national or regional database. Variation of allele probabilities among the relevant populations is quantified by the population structure quantity FST and this quantity affects matching proportions. Matching within a population can be interpreted only with respect to matching between populations and we show here that FST, can be estimated from sample allelic matching proportions within and between populations. We report such estimates from data we extracted from 250 papers in the forensic literature, representing STR profiles at up to 24 loci from nearly 500,000 people in 446 different populations. The results suggest that theta values in current forensic use do not have the buffer of conservatism often thought.
authors.affiliation: Environmental and Scientific Research Ltd., Auckland, New Zealand; National Institute of Standards and Technology, Gaithersburg, MD, USA.
authors.forename: John
authors.initials: J
authors.lastname: Buckleton
authors.affiliation: Department of Statistics, University of Auckland, Auckland, New Zealand.
authors.forename: James
authors.initials: J
authors.lastname: Curran
authors.affiliation: Department of Ecology and Evolution, UNIL-Sorge, Lausanne, Switzerland.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Goudet
authors.affiliation: Forensic Science South Australia, Adelaide, SA, Australia; School of Biological Sciences, Flinders University, Adelaide, SA, Australia.
authors.forename: Duncan
authors.initials: D
authors.lastname: Taylor
authors.affiliation: Bioinformatics Core Facility, Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Thiery
authors.affiliation: Department of Biostatistics, University of Washington, Seattle, WA, USA.
authors.forename: B S
authors.initials: BS
authors.lastname: Weir
mesh_terms: D016172:DNA Fingerprinting; D005787:Gene Frequency; D005819:Genetic Markers; D005828:Genetics, Population; D006801:Humans; D018895:Microsatellite Repeats; D025341:Principal Component Analysis; D011338:Probability Theory; D044469:Racial Groups / Q000235:genetics*
chemical_list: D005819:Genetic Markers
keywords: Coancestry; Forensic DNA; STR marker; Theta