Project description:Forensic body fluid identification is important for crime scene reconstruction. We used Illumina HumanMethylation 450K bead array containing over the 450,000 CpG sites in 16 body fluid samples to find novel DNA methylation marker for forensic body fluid identification. Examination of genome-wide DNA methylation profiling in 16 body fluid samples
Project description:Forensic body fluid identification is important for crime scene reconstruction. We used Illumina HumanMethylation 450K bead array containing over the 450,000 CpG sites in 16 body fluid samples to find novel DNA methylation marker for forensic body fluid identification.
Project description:This research highlights the importance of combining genomics and metabolomics to advance our understanding of the chemical diversity underpinning fungal signaling and communication.
Project description:In this study, we performed miRNA profiling of nucleus accumbens (NAc) and ventral tegmental area (VTA) in MDMA users and control postmortem human brains, which were obtained from Council of Forensic Medicine (Istanbul). According to the microarray analysis of significantly differentially expressed miR-1202 and miR-7975 were selected for further validation using quantitative reverse-transcription PCR (qRT-PCR). qRT-PCR analysis demonstrated that the expression level of miR-7975 was significantly lower in 30 VTA region of MDMA samples compared to 30 control samples. Another significantly deregulated miR-1202 was down-regulated in 30 NAc region of MDMA samples in comparison to 30 control samples. To the best of our knowledge, this is the first study demonstrating that changes in miRNA expression levels are associated with postmortem MDMA users’ brains. Alteration of these miRNAs can serve as novel biomarkers for prediction of MDMA addiction. Our findings suggest that certain differentially expressed miRNAs in MDMA seeking behavior can be used as diagnostics and therapeutic markers.
Project description:Identifying the type and origin of biological samples left at a crime scene is crucial in forensic investigations as it can provide important clues for crime scene reconstruction and linkages between victim/perpetrator/scene. MicroRNAs (miRNAs) are considered to be more stable than mRNA due to their small size and protection by protein and have been demonstrated to be a viable tool for body fluid identification in forensic casework. To screen reliable body-fluid specific miRNAs, ten arrays were performed in five body fluids (peripheral blood, menstrual blood, saliva, semen and vaginal secretion). Two arrays were carried out for each body fluid: three samples for the first and the other two for the second (for menstrual blood, the second array detected three samples).
Project description:Obtaining forensically relevant information beyond who deposited a biological stain on how and under which circumstances it was deposited is a question of increasing importance in forensic molecular biology. In the past few years, several studies have been produced on the potential of gene expression analysis to deliver relevant contextualizing information, e.g. on nature and condition of a stain as well as aspects of stain deposition timing. However, previous attempts to predict the time-of-day of sample deposition based on the differential expression of a limited number of previously known circadian oscillators were of limited success. Herein, we newly approached this goal by applying current sequencing technologies and statistical methods to identify novel candidate markers for forensic time-of-day predictions from whole transcriptome analyses. To this purpose, we collected whole blood samples from ten individuals at eight different time points throughout the day, performed whole transcriptome sequencing and applied biostatistical algorithms for differential gene expression in combination with forensically relevant filtering criteria to identify 81 mRNA markers with significantly differential expression as candidates to predict the time of day. In addition, we assessed the characteristics of a subset of 13 candidate predictors in dried and aged blood stains. While we demonstrated the general possibility of using the selected candidate markers to predict time-of-day of sample deposition, we also observed notable variation between different donors and storage conditions, highlighting the relevance of employing accurate quantification methods in combination with robust normalization procedures. This study’s results are foundational and may be built upon when developing a targeted assay for time-of-day predictions from forensic blood samples in the future.
Project description:Purpose: RNA analysis of post-mortem tissues, or thanathotranscriptomics, has become a topic of interest in forensic science due to the essential information it can provide in forensic case investigations. Several studies have previously investigated the effect of death on gene transcription, but it has never been conducted with samples of the same individual. Methods: For the first time, a longitudinal mRNA expression analysis study was performed with post-mortem human blood samples from individuals with a known time of death. Results: The results reveal that, after death, two clearly differentiated groups of up- and down-regulated genes can be detected. Pathway analysis suggests active processes, rather than passive degradation, are the source of early post-mortem changes of gene expression in blood. In addition, a generalised linear model with an elastic net restriction predicted post-mortem interval with an RMSE of 4.88 hours. Conclusions: Although promising, the forensic relevance of the model is currently limited and should be further improved in more extended studies.