Browsing by Author "Courts, Cornelius"
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- Body fluid identification and donor association of mock case samples: Results of two EDNAP collaborative exercisesPublication . Hänggi, Nadescha; Amorim, António; Afonso Costa, Heloísa; D. Andersen, Jeppe; Morling, Niels; Kampmann, Marie-Louise; Courts, Cornelius; Gosch, Annica; Neis, Maximilian; Syndercombe Court, Denise; Giangasparo, Federica; Elida Fonneløp, Ane; Johannessen, Helen; Hadrys, Thorsten; Parson, Walther; Niederstätter, Harald; Sidstedt, Maja; Sijen, Titia; van den Berge, Margreet; Hanson, Erin; Ballantyne, Jack; Haas, CordulaThe European DNA Profiling Group (EDNAP) has previously evaluated the performance, robustness, and reproducibility of various mRNA markers for identifying body fluids using capillary electrophoresis (CE) and massively parallel sequencing (MPS) methods. MPS of mRNA targets is used for body fluid identification and provides information on who contributed which body fluid to a binary mixture, thereby adding important contextual aspects to a crime scene investigation. The analysis of coding region SNPs (cSNPs) in body fluid-specific transcripts allows the association of an individual’s DNA cSNP profile with the body fluid-specific RNA cSNP genotype. The Zurich Institute of Forensic Medicine in Switzerland organized two consecutive collaborative exercises within the EDNAP group to evaluate the performance of two targeted mRNA sequencing assays: the BSS cSNP assay (for blood, saliva, and semen) and the 6F cSNP assay (for six fluids/tissues, including BSS and additionally vaginal secretion, menstrual blood, and skin). Each cSNP RNA assay was accompanied by a genomic DNA assay to genotype the cSNPs in the person(s) of interest. Eleven laboratories participated in one or both of the EDNAP collaborative exercises. In each exercise, 16 mock case samples were provided by the organizers, and the laboratories could analyze additional, self-prepared stains. Participants could use either the Ion S5 or the MiSeq sequencing platform. Here, we present the compiled results of the two collaborative exercises. We investigated DNA and RNA yields, STR profiles, and RNA profiles for body fluid identification and body fluid - donor association. While the mock case samples provided information on the performance of the assays, the self-prepared stains were a blind test for the organizers to identify the body fluids and the contributors.
- mRNA profiling and donor association of mock casework samples: Results of a 3rd and 4th EDNAP collaborative exercisePublication . Hänggi, Nadescha Viviane; Amorim, António; Afonso Costa, Heloísa; Andersen, Jeppe Dyrberg; Kampmann, Marie-Louise; Courts, Cornelius; Neis, Maximilian; Syndercombe-Court, Denise; Giangasparo, Federica; Fonneløp, Ane Elida; Johannessen, Helen; Hadrys, Thorsten; Fürst, Angelika; Parson, Walther; Niederstätter, Harald; Sidstedt, Maja; Aili Fagerholm, Siri; Sijen, Titia; van den Berge, Margreet; Hanson, Erin; Ballantyne, Jack; Haas, CordulaSimultaneous identification and association of body fluids to donors can serve as a powerful tool in the criminal investigation of mixed traces. Massively parallel sequencing of mRNA targets not only identifies the origin of the body fluids but may also provide additional contextual information about the body fluid donors of a (binary) mixture using coding region SNPs (cSNPs). Within the European DNA Profiling Group (EDNAP), two consecutive collaborative exercises (3rd and 4th EDNAP exercise) were organized, with the objective to evaluate the performance of two previously published high-resolution mRNA sequencing assays. In the 3rd EDNAP exercise, the BFID-cSNP-BSS assay (cSNPs for blood, saliva, and semen) was evaluated, while in the 4th EDNAP exercise, the BFID-cSNP-6F assay (cSNPs for six fluids/tissues, including blood, saliva, semen, vaginal secretion, menstrual blood, and skin) was tested. Each RNA cSNP assay was accompanied by a genomic DNA assay for the genotyping of the cSNPs in the individual(s) or body fluid donor(s) of interest. A total of 11 laboratories participated in one or both collaborative exercises. In each exercise, the participating laboratories received a set of 16 standardized mock case stains for analysis and were encouraged to analyze additional, self-prepared stains and reference samples. Laboratories could participate using either the Ion Torrent S5™ or the Illumina MiSeq™ sequencing system. The results of the 16 mock case stains were very encouraging in both exercises, as body fluid components could be reliably identified for most of the stains. Since successful donor association depends on the number of body fluid markers covered in the sequencing results, we found that for stains consisting of blood, menstrual blood, vaginal secretion or a mixture thereof, the cSNPs provided substantial genetic discriminatory information for successful association of the respective body fluid to its donor. In mixtures, the difficulty in interpreting the cSNP genotypes might be attributed to the masking effect of the other body fluid(s) present. Body fluid identification and donor association of skin samples proved to be a significant challenge. In conclusion, body fluid identification and donor association using the BFID-cSNP-BSS and -6 F assays is a promising and effective method across laboratories and sequencing platforms.