STRidER STRs for identity ENFSI Reference database
The European Network of Forensic Science Institutes DNA Working Group (ENFSI DNA WG) provides an updated version to the previously published 'ENFSI DNA WG STR Population Database'. The concept of STRidER (STRs for identity ENFSI Reference database) is still based on the considerations detailed in 1, but the dataset was updated to comply with the technical developments and adaptation of additional STR markers 2.
The task of this website is to make STRidER generally available to forensic laboratories. This website can be used to calculate match probabilities of DNA profiles from high-quality cosmopolitan Caucasian populations across Europe. Additional populations will be added in the future. The online platform is work in progress and additional features will continuously become available 3.
This project was supported by HOME/2010/ISEC/MO/4000001759 (STEOFRAE).
STR loci and allele nomenclature
STRidER holds STR loci defined in the specifications of the ENFSI DNA WG. These include the STR loci D3S1358, VWA, D16S539, D8S1179, D21S11, D18S51, D2S441, D19S433, TH01, FGA, D22S1045, SE33, D10S1248, D1S1656, D12S391, and D2S1338. Additional loci may be included in the future based on the availability of high quality population data. Loci that are included in commercial kits but not in this version of STRidER, as no high quality population data are available, are dimmed in the input display.
As defined by the ENFSI DNA WG the following criteria for allele nomenclature are applied:
- In general, allele nomenclature complies with the guidelines published by the DNA Commission of the International Society of Forensic Sciences 4.
- The query of plausible allele values leads to meaningful results, other values are not accepted or may lead to false or biased results.
- Heterozygote allele calls shall be entered by using the lower value for the first field of a locus and the higher value for the second field (e.g. 24/25; NOT 25/24). Multiple allele entries (e.g. mixtures) into one single cell are not accepted.
- Homozygote allele values need to be specified twice, making use of both fields of a locus (e.g. 14/14; NOT 14). Single empty fields are not accepted.
- Rare alleles can be entered using the „1/99“ nomenclature. Here, „1“ represents a rare allele outside the accepted allele categories that is lower than the other allele value (e.g. 1/25; NOT 25/1). The value „99“ represents the higher rare allele (e.g. 27/99; NOT 99/27). When the true allele length is known, it should be used instead of "1" or "99".
We defined the following allele category ranges taking the different allelic ladders into consideration:
References
1 Gill P, Foreman L, Buckleton JS, Triggs CM, Allen H (2003) A comparison of adjustment methods to test the robustness of an STR DNA database comprised of 24 European populations; Forensic Science International 131:184-96
2 Welch LA, Gill P, Phillips C, Ansell R, Morling N, Parson W, Palo JU, Bastisch I (2012) European Network of Forensic Science Institutes (ENFSI): Evaluation of new commercial STR multiplexes that include the European Standard Set (ESS) of markers; Forensic Sci Int Gen 6:819–826
3 Bodner M, Bastisch I, Butler JM, Fimmers R, Gill P, Gusmão L, Morling N, Phillips C, Prinz M, Schneider PM, Parson W (2016) Recommendations of the DNA Commission of the International Society for Forensic Genetics (ISFG) on quality control of autosomal Short Tandem Repeat allele frequency databasing (STRidER); Forensic Sci Int Gen 24:97-102
4 Bär W., Brinkmann B., Budowle B., Carracedo A., Gill P., Lincoln P., Mayr W., Olaisen B. (1997), 'DNA recommendations. Further report of the DNA Commission of the ISFG regarding the use of short tandem repeat systems.', Forensic Science International 87(3), 179-184.