Forensic botany can provide significant supporting evidence during criminal investigations. However, it is still an underutilized field of investigation with its most common application limited to identifying specific as well as suspected illegal plants. The ubiquitous presence of plant species can be useful in forensics, but the absence of an accurate identification system remains the major obstacle to the present inability to routinely and correctly identify trace botanical evidence. Many plant materials cannot be identified and differentiated to the species level by traditional morphological characteristics when botanical specimens are degraded and lack physical features. By taking advantage of a universal barcode system, DNA sequencing, and other biomolecular techniques used routinely in forensic investigations, two chloroplast DNA regions were evaluated for their use as "barcoding" markers for plant identification in the field of forensics. We therefore investigated the forensic use of two non-coding plastid regions, psbA-trnH and trnL-trnF, to create a multimarker system for species identification that could be useful throughout the plant kingdom. The sequences from 63 plants belonging to our local flora were submitted and registered on the GenBank database. Sequence comparison to set up the level of identification (species, genus, or family) through Blast algorithms allowed us to assess the suitability of this method. The results confirmed the effectiveness of our botanic universal multimarker assay in forensic investigations.

Conventional methods for forensic species identification are mainly based on immunological procedures, which have limited applications for old and degraded specimens. The mitochondrial cytochrome b gene sequence has emerged in forensics among molecular methods. Recent investigations in the taxonomic field have suggested that a DNA-based identification system may aid the resolution of animal diversity and classification using sequence analysis and phylogenetic links. Selected gene sequences can be viewed as a genetic "barcode," which is enclosed in every cell, and barcoding is a standardized approach for characterizing species using short DNA sequences as a diagnostic biomarker for organisms. The aim of this study was to evaluate the potential of barcode mitochondrial genes, such as the cytochrome c oxidase sub 1 (COI) and the 16S rRNA gene, as a forensic tool. We developed a new approach for species testing and identification with a singleplex PCR amplification that will be useful not only in criminal casework but also in biosecurity, food authentication, investigation against poaching or illegal trade of endangered species, and wildlife enforcement. Seven fragments ranging from 157 to 541 bp (base pairs) in humans were selected from COI and 16S rRNA genes by different redesigned sets of primers suitable for forensic purposes. The specificity of each primer pair was evaluated with a single PCR reaction on different substrates, and the diversity values were calculated by statistical tests to select a set of markers that could be useful in different caseworks. A case example of forensic species identification is also presented.

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Estimation of the time since death is a practical task in daily forensic casework but available methods lack reliability especially in complex deaths and after long PM period. MirRNA analysis should be ideally an useful ancillary tool as it proved to be sensitive in forensics especially for body fluid identification.\ud Here we analyzed 10 miRNAs with a supposed role in circadian rhythms through an RT-qPCR assay in postmortem samples of blood (n = 12) and vitreous humor (n = 12) from individuals died in the day or at night, in order to find those with an oscillating pattern of variation. The expression stability of four endogenous controls was also tested to find the most suitable for normalization.SNORD95 proved to be the best and was used in both body fluids. Four miRNAs showed significant differential expression between individuals died at daytime and at nighttime, mir-106b and mir-96 in vitreal samples and mir-142-5p and mir-219 in blood. Results are preliminary and limited to the small sample set. Future studies on more samples and with additional markers are needed to further elucidate the role of miRNA profiling in postmortem contexts and how useful they would be as “chronobiomarkers” for time of death determinatio

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