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STR Allele Sequence Variation: Current Knowledge and Future Issues



Katherine Gettings, Rachel A. Aponte, Peter Vallone, John M. Butler


This article reviews what is currently known about short tandem repeat (STR) allelic sequence variation in and around the twenty-four loci most commonly used throughout the world to perform forensic DNA investigations. These STR loci include D1S1656, TPOX, D2S441, D2S1338, D3S1358, FGA, CSF1PO, D5S818, SE33, D6S1043, D7S820, D8S1179, D10S1248, TH01, vWA, D12S391, D13S317, Penta E, D16S539, D18S51, D19S433, D21S11, Penta D, and D22S1045. All known reported variant alleles are compiled along with genomic information available from GenBank, dbSNP, and the 1000 Genomes Project. Supplemental files are included that provide annotated reference sequences for each STR locus, characterize genomic variation around the STR repeat region, and compare alleles present in currently available STR kit allelic ladders. Looking to the future, STR allele nomenclature options are discussed as they relate to next generation sequencing efforts underway.
Forensic Science International: Genetics


forensic DNA, short tandem repeat, STR loci, DNA database, sequence variation, STR nomenclature


Gettings, K. , Aponte, R. , Vallone, P. and Butler, J. (2015), STR Allele Sequence Variation: Current Knowledge and Future Issues, Forensic Science International: Genetics, [online], (Accessed April 21, 2024)
Created July 5, 2015, Updated November 10, 2018