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Establishing the cellular or tissue-type origin of human biological traces found at crimes scenes is forensically relevant, as it allows evaluating the crime relevance of such traces and enables reconstructing the sequence of crime events. Messenger RNA and micro RNA markers are useful for forensic tissue identification, but provide challenges for linking RNA-identified cell/tissue types with DNA-identified trace donors, especially in mixed traces. DNA methylation markers overcome this problem, but provide technical challenges due to the DNA treatment required by most analysis methods. Here we introduce a novel type of DNA markers for forensic tissue identification analysed without prior DNA treatment, namely copy number variation (CNV). Using genome-wide CNV screening followed-up by targeted qPCR confirmation, and using qPCR analysis of additional CNV-like candidate DNA markers, in samples of several individuals from all commonly encountered forensically-relevant tissue types, we identified DNA markers specific for blood and semen, respectively. Preliminary forensic validation testing demonstrates that the developed qPCR assays are highly sensitive - delivering positive results down to picogram level of input DNA, specific, and can cope well with degraded DNA, providing suitable prerequisites for forensic applications. Moreover, we exemplified that using the CNV qPCR products as input material for subsequent forensic STR analysis delivered full STR profiles, opening-up new avenues of using the same DNA aliquot for both forensic purposes, tissue and individual identification. Provided additional forensic validation studies, we envision the application of these novel DNA markers for forensic tissue identification in future forensic casework. Such CNV markers are particularly useful for tissue identification in old/cold cases, where aged/old DNA extracts are available that contain no RNA and are not suitable for DNA methylation analysis due to limited DNA quantity and quality.

Albert is a dog (Canis familiaris), but he does not realize this. Albert loves human food (and beer), watching movies on the internet, sleeping in bed, and more. But he should not do all these things. To convince him that, we have desinged a test procedure. The DEFB1 gene is unique to human species. Detecting its presence from saliva and in short periods may offer an advantage in the field of forensic medicine, and influence Albert’s bad habits. This study reveals novel utilization of the multisine impedance spectroscopy carried out during potentiodynamic polarization (pDEIS) of the electrode. We have utilized pDEIS to detect DEFB1 gene in collected saliva samples. The detection process was conducted at the boron-doped diamond surfaces functionalized with DEFB1-complimentary oligonucleotide sequence, anchored at the electrode surface. Next, a short-term electrode incubation in presence of target DNA sample allows for achieving DNA hybridization when exposed to human DNA material. The dsDNA orientation vs electrode surface is affected by polarization, and tracked by changes in the electrode kinetics preceded by subtle capacitance dispersion effects. The optimized measurement conditions range between +0.5 and +0.9 V vs Ag|AgCl due to nonspecific DNA adsorption, affecting heterogeneous charge transfer. The DNA hybridization is not achieved in the case of non-complimentary ssDNA originated from any other species subjected to this test. The discussed differences obtained during electrode incubation are supported by the XPS analyses.

Background: Several studies confirmed the predictive role on treatment outcome of interim-PET after 2nd ABVD cycle (iPET2) in Hodgkin lymphoma (HL). We hypothesized that interim PET after 1st cycle (iPET1) might define chemosensitivity with a better accuracy than iPET-2. To test this hypothesis, PLRG launched in 2008 a prospective multicenter observational study aiming at assessing the prognostic role of iPET1 and the dynamic of sequential PET response to ABVD. Methods: Adult pts with newly diagnosed early (stage I-IIA) and advanced (stage IIB-IV) consecutively enrolled in 11 Polish centers were risk-stratified by the EORTC/GELA criteria and treated according to the ESMO guidelines: ABVD x 3-4 cycles + IFRT in early stage, ABVD x 6 ± consolidation RT in advanced stage disease. Patients were scanned with iPET1 and iPET2 and no treatment change was permitted based solely on iPET results, with the exception of clinical or radiological evidence of overt HL progression. After the first interim analysis (52 pts enrolled, 2010), which demonstrated that all the iPET1 negative patients had also a negative iPET2, the protocol was amended, limiting the iPET2 scans only to pts with iPET1 Deauville score 5,4,3. Quality control for PET-CT was supervised by the Italian-Polish core lab using a standard methodology. PET scans were interpreted locally according to the Deauville 5-point scale: Score 1 to 3, was considered a negative (-), score 4 to 5 a positive (+) scan. Subsequently all PET scans were uploaded to the web platform WIDEN® for central review and Italian-Polish expert panel (EP) scored them afresh. Discorcondant cases were discussed in a joint review session with all the five EP members. Binary and overall concordance rates were calculated using k Cohen's and alpha Krippendorf's coefficients, respectively. Negative (NPV) and positive predictive values (PPV) of iPET1 were calculated using time to progression free survival (PFS) event. Results: Between 2008 and 2014, 346 pts were registered. 35 pts were excluded from the analysis for absence/poor quality of images resulting in 108(35%) assessable pts with early and 203(65%) with advanced HL. Median age at diagnosis was 31(18-80) years. iPET1 was scored 1-3 in 87/108(81%), and 4-5 in 21/108(19%) of pts with early and in 133/203(65%), and 70/203(35%) with advanced stage, respectively. Out of 91pts with positive iPET1, 83 pts underwent iPET2, which remained (+) in 41/83(49,4%) pts. In 22 pts treatment was escalated. 11 of those pts, in whom the treatment escalation was decided solely on positive iPET were excluded from the analysis; the remaining had symptoms or CT evidence of progression. After a median follow-up of 40,2 (3,2-90,2) months 300 pts (103 "early" and 197 "advanced") were evaluable. 65(21,7%) of them (9 in early and 56 in advanced group) had a PFS event: in "early" group 9(9%) showed disease progression (4 with iPET1(-) and 5 with IPET1(+)) and 1 of them died. In advanced stage 49(25%) pts showed disease progression (16 with iPET1(-) and 33 withiPET1(+)) out of whom 13 died; 7 additional pts died without HL progression: 4 from toxicity and 3 from unrelated events. At 36 months NPV and PPV of iPET1 was 93% and 45% in "early" and 81% and 52% in "advanced" group, respectively. The dynamic of response to ABVD was assessed in 189 pts who underwent both iPETs. All 116 pts with iPET1(-) remained (-) in iPET2-(fast-responders). Out of 83pts with IPET1(+) 39 (47%) became iPET2(-)-(slow responders); the rest (34pts: 41%) remained iPET2(+)-(no responders). PFS for fast-responders @36 months was 85%, for slow-responders 80% (log rank p=0,36) and for no-responders 25% (log rank p=0,0000). The EP changed the local iPET1 score in 27 cases: in 14 from (+) to (-) in 13 from (-) to (+). The inter-observer-agreement among reviewers on evaluating a positive vs. negative interim PET scans was good, Fleiss' kappa = 0.73, comparable to that found in analogous studies (IVS, HD0607). Conclusion: iPET1 fails to better identify chemosensitivity in ABVD-treated HL compared to iPET2. PPV of iPET1 is substantially inferior to the published results for iPET2. However NPV of iPET1 is comparable to iPET2 and therefore might guide early treatment de-escalation strategies. Disclosures Zaucha: Roche: Honoraria, Research Funding, Speakers Bureau; Amgen: Honoraria, Research Funding, Speakers Bureau; Takeda: Honoraria, Speakers Bureau. Knopinska-Posluszny:Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Speakers Bureau; Teva: Other: travel, accommodation, Speakers Bureau. Walewski:Mundipharma; Roche; Takeda: Honoraria, Other: Travel expenses; Amgen; Boehringer Ingelheim; Celgene; Janssen-Cilag; Mundipharma; Roche; Takeda; Teva: Consultancy; Bayer (Inst); Bayer/Onyx (Inst); Boehringer Ingelheim (Inst); Celgene (Inst); Celltrion (Inst); Gilead Sciences (Inst); GlaxoSmithKline (Inst); GlaxoSmithKline (Inst); Mundipharma (Inst); Pfizer (Inst); Roche (Inst); Roche/Genentech (Inst); Seattle Geneti: Research Funding.