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Estimation of population specific values of theta for sequence-based STR profiles

NCJ Number
Forensic Science International Genetics Volume: 68 Dated: January 2024
Date Published
January 2024

This paper highlights estimates of theta values from sequencing data for five global metapopulations, which inform probabilities for autosomal short tandem repeats (STRs) in forensic casework; and it reports that estimates are less than one percent for most metapopulations and less than two percent for the Native American metapopulation.


In this article, the authors describe the estimation of θ (theta) values from autosomal STR sequencing data for five metapopulations. The data were compiled from 20 publications and included 39 datasets comprising a total of 7005 samples. The estimates are suitable for use within the calculation of match probabilities in forensic casework. They also have constructed a phylogenetic tree using this data that aligns with our understanding of human evolution. (Published Abstract Provided)

Date Published: January 1, 2024