Kit-dependent discrepancy in D16S539 and general considerations for database matches.

Throughout the last decade more companies have been offering multiplex PCR kits for forensic STR typing. As a consequence, it has been demonstrated, that an observed genotype may unexpectedly vary at a single locus when different STR kits have been used. Analysing STR profiles which have to be entered in a national database, unknown or undetected primer binding site mutations, insertions or deletions within the flanking region of STR loci may hinder matches and therefore have far-reaching consequences. The current study is a further example indicating that sequence variations in flanking regions are a common problem within STR typing which should not be underestimated. A deletion of 16 nucleotides close to the primer binding site downstream of the repeat sequence resulted in deviant genotypes at the D16S539 locus according to different STR kits used.

Application of DNA barcoding for identifying forensically relevant Diptera from northern Thailand.

In recent decades, forensic entomology has become a useful tool in criminal investigations all over the world. Species-specific identification of flies plays an important role in this field and is obligatory for accurate calculation of the post-mortem interval. However, not all important colonizers of a corpse can be identified by common morphological keys. Due to similar morphology and the lack of keys for some taxa, especially for immature stages, DNA barcoding has become more popular during the last recent years. This development is particularly important for countries like Thailand, in which forensic entomology is a newly developing research area and which faces several challenges such as a high biodiversity of fly species. The most commonly used barcoding region in forensic entomology, the mitochondrial cytochrome oxidase subunit 1 (coI) gene, as well as a 1000-bp-long region of the 28S nuclear rRNA gene, was used to analyze and establish the molecular barcodes of 13 different species of flies of forensic relevance in northern Thailand.

Molecular identification and phylogenetic analysis of the forensically important family Piophilidae (Diptera) from different European locations.

Species identification plays an important role in forensic entomology and is mandatory for an accurate calculation of the minimum post-mortem interval. Many important Diptera and Coleoptera taxa of the cadaver community can already be identified by common barcoding approaches, i.e., by sequencing a 658bp region in the mitochondrial cytochrome c oxidase subunit I (coI) gene. Nevertheless, there is still a lack of reference barcodes for species, in particular, that can be found on cadavers at later decomposition stages. Flies of the family Piophilidae illustrate this gap of knowledge perfectly. Due to the fact that a reliable morphological identification key for the immature stages of this flies is still missing and the immature stages of many piophilids cannot be assigned to a certain species, there is need for additional tools to identify forensically relevant taxa. We collected adult piophilid specimens at 10 locations in five European countries: Spain (n=3 locations), Germany (n=3), Portugal (n=2), Poland (n=1) and Switzerland (n=1). Apart from the coI barcoding region, we additionally analyzed a 398bp long region of the nuclear elongation factor 1 alpha (ef1a) and subsequently established the molecular identifier for nine piophilid species. In addition, we present the molecular phylogeny of the examined taxa.